--- title: "Web Hosting & WordPress Glossary | Hosterwise" description: "TTFB, LSCache, DNS, SPF, DKIM, EPP code… 58 web hosting and WordPress terms explained in plain words, with our guides." url: https://hosterwise.com/en/glossary/ language: en updated: 2026-10-15 source: Hosterwise translations: fr: https://hosterwise.com/glossaire.md --- Canonical page: # Web hosting and WordPress glossary 58 technical terms explained in a few lines: web servers, caching, DNS, e-mail, security, domain names and performance. Each definition links to our guides so you can dig deeper. 58 terms defined · Updated October 12, 2026 ## Topics ### Performance 18 - CDN - CLS - Core Web Vitals - Gzip and Brotli compression - HTTP/2 - HTTP/3 - INP - Lazy loading - LCP - LSCache - Object cache - OPcache - Page cache - Point of presence (PoP) - QUIC - QUIC.cloud - Reverse proxy - TTFB ### Servers and hosting 11 - Bandwidth - Cloud hosting - Control panel - Inode - LiteSpeed - PHP-FPM and LSAPI - Shared hosting - SLA - SSH - Uptime - VPS ### WordPress 4 - 301 redirect - Permalink - Staging site - WP-Cron ### DNS and e-mail 11 - A and AAAA records - CNAME record - DKIM - DMARC - DNS - DNS propagation - MX record - Name server - SPF - TTL - TXT record ### Domain names 8 - Domain extension (TLD) - Domain transfer - EPP code - IDN (internationalised domain name) - RDAP - Registrar - Registry - WHOIS ### Security 6 - 3-2-1 backup - HTTPS - Let’s Encrypt - SSL/TLS - Two-factor authentication (2FA) - WAF (web application firewall) ## 0–9 Back to the index ### 3-2-1 backup Security The 3-2-1 rule is the benchmark for backups: keep 3 copies of your data, on 2 different media, with 1 of them off-site, meaning somewhere other than the server that hosts the site. That way a failure, an attack or a mistake cannot wipe out both the site and its backups. Also known as: 3-2-1 rule, 3-2-1 backup rule, 3-2-1 strategy Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: Staging site WAF (web application firewall) ### 301 redirect WordPress A 301 redirect tells browsers and search engines that a page has moved to a new address for good. Visitors are sent to the new URL automatically and Google carries most of the old page’s signals over to it. It is essential after changing your URL structure or domain name, or moving to HTTPS. Also known as: 301 redirects, permanent redirect Learn more: [How to Migrate a WordPress Site With Zero Downtime](https://hosterwise.com/en/blog/migrate-wordpress-site/) [Free migration](https://hosterwise.com/en/free-migration/) See also: Permalink HTTPS ## A Back to the index ### A and AAAA records DNS and e-mail An A record maps a domain or subdomain to an IPv4 address, for example 203.0.113.10; an AAAA record does the same with an IPv6 address. They tell the world which server your site lives on, so they are the records you change when you switch hosts. Also known as: A record, A records, AAAA record, AAAA records Learn more: [How to Migrate a WordPress Site With Zero Downtime](https://hosterwise.com/en/blog/migrate-wordpress-site/) [Domain names](https://hosterwise.com/en/domain-names/) See also: DNS CNAME record TTL ## B Back to the index ### Bandwidth Servers and hosting Bandwidth is the amount of data a server can send to visitors; hosting companies often use the word for the monthly traffic allowance. Every page, image or video displayed uses some of it, and browser caching, compression and a CDN all reduce it. Hosterwise plans include unlimited traffic. Also known as: monthly traffic Learn more: [Pricing](https://hosterwise.com/en/pricing/) [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: CDN Gzip and Brotli compression ## C Back to the index ### CDN Performance A CDN (Content Delivery Network) is a network of geographically spread servers that keep a copy of your site’s files: images, CSS, JavaScript and sometimes whole pages. Each visitor is served by the nearest point of presence, which cuts latency and takes load off the origin server during traffic spikes. Also known as: Content Delivery Network, content delivery network Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: QUIC.cloud Reverse proxy Point of presence (PoP) TTFB ### Cloud hosting Servers and hosting Cloud hosting runs a site on virtualised infrastructure whose resources can be scaled up or down on demand, sometimes billed by usage. The label covers very different products, from a plain virtual server to a fully managed platform: for WordPress, the configuration and the support matter more than the name. See also: VPS Shared hosting ### CLS Performance CLS (Cumulative Layout Shift) measures the visual stability of a page: it adds up unexpected content shifts during the visit, caused for instance by an image without dimensions, a web font or a banner injected above the text. Google rates a score below 0.1 as good. Also known as: Cumulative Layout Shift Learn more: [WordPress Core Web Vitals: Diagnose and Fix LCP, INP and CLS](https://hosterwise.com/en/blog/wordpress-core-web-vitals/) See also: Core Web Vitals Lazy loading ### CNAME record DNS and e-mail A CNAME (Canonical Name) record makes one name an alias of another domain name: www.example.com can point to example.com or to a third-party service’s address. A CNAME cannot coexist with other records on the same name, which is why it is not used at the root of a domain. Also known as: CNAME Learn more: [Domain names](https://hosterwise.com/en/domain-names/) See also: A and AAAA records DNS ### Control panel Servers and hosting A control panel is the web interface you use to manage hosting without the command line: sites, domain names, databases, e-mail accounts, SSL certificates and backups. Hosterwise uses CyberPanel, a panel built for LiteSpeed servers that installs WordPress in a few clicks. Also known as: CyberPanel, hosting panel Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: Shared hosting LiteSpeed SSH ### Core Web Vitals Performance Core Web Vitals are three metrics defined by Google to measure what real visitors experience: LCP for loading, INP for responsiveness and CLS for visual stability. They are computed from real Chrome user visits (the CrUX report) and are part of the page experience signals Google Search takes into account. Learn more: [WordPress Core Web Vitals: Diagnose and Fix LCP, INP and CLS](https://hosterwise.com/en/blog/wordpress-core-web-vitals/) [Speed Up WordPress: 15 Practical Actions That Work](https://hosterwise.com/en/blog/speed-up-wordpress/) See also: LCP INP CLS ## D Back to the index ### DKIM DNS and e-mail DKIM (DomainKeys Identified Mail) adds a cryptographic signature to every e-mail, checked against a public key published in the domain’s DNS as a TXT record such as selector.\_domainkey.example.com. The recipient can thus confirm the message really comes from that domain and was not altered on the way. Also known as: DomainKeys Identified Mail See also: SPF DMARC ### DMARC DNS and e-mail DMARC tells mailbox providers what to do with an e-mail that fails SPF and DKIM checks: let it through (p=none), send it to spam (p=quarantine) or reject it (p=reject). Published as a TXT record on \_dmarc.your-domain.com, it also lets you receive reports. Since February 2024, Gmail has required it from senders of more than 5,000 messages a day. See also: SPF DKIM ### DNS DNS and e-mail DNS (Domain Name System) is the internet’s directory: it translates a domain name such as hosterwise.com into the IP addresses computers can reach. A domain’s information lives in its DNS zone, as records (A, AAAA, CNAME, MX, TXT…) served by its name servers. Also known as: Domain Name System, DNS zone Learn more: [Domain names](https://hosterwise.com/en/domain-names/) [How to Migrate a WordPress Site With Zero Downtime](https://hosterwise.com/en/blog/migrate-wordpress-site/) See also: Name server TTL A and AAAA records ### DNS propagation DNS and e-mail DNS propagation is the time it takes for a DNS change to be seen everywhere. Nothing is actively pushed: resolvers keep the old answer cached until its TTL expires. A new IP address shows up within minutes to a few hours, while a change of name servers can take up to 48 hours. Learn more: [How to Migrate a WordPress Site With Zero Downtime](https://hosterwise.com/en/blog/migrate-wordpress-site/) [Free migration](https://hosterwise.com/en/free-migration/) See also: TTL Name server ### Domain extension (TLD) Domain names The extension, or TLD (Top-Level Domain), is the last part of a domain name: .com, .fr, .eu… Country-code extensions (ccTLDs) belong to a country or territory, like .fr or .ca, while generic ones (gTLDs) include .com, .net and .org. Each has its own registry and rules. Also known as: TLD, ccTLD, gTLD, top-level domain Learn more: [Domain names](https://hosterwise.com/en/domain-names/) See also: Registry IDN (internationalised domain name) ### Domain transfer Domain names A domain transfer moves a domain name to a new registrar without changing its owner or taking the site offline. You unlock the domain at the current provider, get its EPP code, then order the transfer at the new one. Rules and timings, such as a lock after a recent registration, depend on the extension. Also known as: domain name transfer, transfer a domain, transferring a domain Learn more: [Domain names](https://hosterwise.com/en/domain-names/) See also: EPP code Registrar Name server ## E Back to the index ### EPP code Domain names The EPP code, also called authorisation code or AuthInfo, is a domain name’s own password. The current registrar gives it to the registrant on request, and it is entered when ordering the transfer at the new provider. It ensures that only the registrant can move the domain. Also known as: authorisation code, authorization code, AuthInfo, auth code Learn more: [Domain names](https://hosterwise.com/en/domain-names/) See also: Domain transfer Registrar ## G Back to the index ### Gzip and Brotli compression Performance Gzip or Brotli compression shrinks text files (HTML, CSS, JavaScript, SVG) before they are sent to the browser, which unpacks them instantly. Brotli, designed by Google, usually compresses better than Gzip at a similar speed. It is switched on at server level and needs no change to the site itself. Also known as: Brotli, Gzip, Gzip compression, Brotli compression Learn more: [Speed Up WordPress: 15 Practical Actions That Work](https://hosterwise.com/en/blog/speed-up-wordpress/) See also: CDN Bandwidth ## H Back to the index ### HTTP/2 Performance HTTP/2 is the second major version of the HTTP protocol, published in 2015 (RFC 7540) and revised in 2022 (RFC 9113). It runs many requests in parallel over a single connection, compresses headers and lets resources be prioritised. Browsers only use it over HTTPS. HTTP/3 is its successor. Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: HTTP/3 HTTPS ### HTTP/3 Performance HTTP/3 is the third major version of the HTTP protocol, standardised by the IETF in 2022 (RFC 9114). It runs over QUIC instead of TCP: secure connections open faster and a lost packet no longer holds up the other requests, which helps on mobile networks. LiteSpeed servers support it natively. Learn more: [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) See also: QUIC HTTP/2 LiteSpeed ### HTTPS Security HTTPS is the secure version of HTTP: traffic between the browser and the site is encrypted with TLS, so it cannot be read or altered on the way. It is essential for forms and payments, browsers require it for HTTP/2 and HTTP/3, and Chrome flags plain HTTP pages as “Not secure”. See also: SSL/TLS HTTP/2 301 redirect ## I Back to the index ### IDN (internationalised domain name) Domain names An internationalised domain name (IDN) contains characters outside the basic Latin alphabet, such as é, ü or ç, for example café.fr. Under the hood it is converted into an ASCII form starting with “xn--” (Punycode encoding). Each registry decides which characters its extension accepts. Also known as: IDN, internationalized domain name, internationalised domain name, Punycode Learn more: [Domain names](https://hosterwise.com/en/domain-names/) [.fr domain name](https://hosterwise.com/en/domain-names/fr/) See also: Domain extension (TLD) Registry ### Inode Servers and hosting An inode is the entry that describes a file or folder in the Linux file system: every file uses one, whatever its size. Some hosts cap how many you may use. A WordPress site full of thumbnails, local backups or cache files can hit that cap before it runs out of disk space. Also known as: inodes Learn more: [Pricing](https://hosterwise.com/en/pricing/) [Frequently asked questions](https://hosterwise.com/en/faq/) See also: Shared hosting 3-2-1 backup ### INP Performance INP (Interaction to Next Paint) measures how responsive a page is: the delay between an interaction (click, tap, key press) and the visual update it triggers, across the whole visit. It replaced FID among the Core Web Vitals in March 2024. Google rates it good under 200 milliseconds. Also known as: Interaction to Next Paint Learn more: [WordPress Core Web Vitals: Diagnose and Fix LCP, INP and CLS](https://hosterwise.com/en/blog/wordpress-core-web-vitals/) See also: Core Web Vitals LCP CLS ## L Back to the index ### Lazy loading Performance Lazy loading means downloading images, videos or iframes only when they get close to the visible part of the screen. WordPress has added the loading="lazy" attribute to most images automatically since version 5.5. The main image at the top of the page, however, should never be lazy-loaded. Also known as: lazy load, lazy-load See also: LCP CLS ### LCP Performance LCP (Largest Contentful Paint) measures how long it takes to render the largest visible element of the page, often the hero image or the main heading. Google rates it good under 2.5 seconds. A fast server, a page cache, optimised images and preloading the main image all improve it. Also known as: Largest Contentful Paint Learn more: [WordPress Core Web Vitals: Diagnose and Fix LCP, INP and CLS](https://hosterwise.com/en/blog/wordpress-core-web-vitals/) See also: Core Web Vitals TTFB Lazy loading ### Let’s Encrypt Security Let’s Encrypt is a free, automated and open certificate authority run by the non-profit ISRG. It issues short-lived, domain-validated SSL/TLS certificates that the server renews automatically. It is the reason HTTPS has become free on most hosting plans. Also known as: Let's Encrypt See also: SSL/TLS HTTPS ### LiteSpeed Servers and hosting LiteSpeed Web Server is an HTTP server built by LiteSpeed Technologies as an alternative to Apache and Nginx. Its event-driven design handles many connections with little memory, it reads Apache .htaccess files and it ships with a built-in page cache (LSCache) and HTTP/3. Hosterwise runs the commercial edition, LiteSpeed Enterprise, with ESI. Also known as: LiteSpeed Web Server, LiteSpeed Enterprise, LiteSpeed server, LiteSpeed servers Learn more: [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) [LiteSpeed vs Nginx vs Apache: Which Web Server for WordPress?](https://hosterwise.com/en/blog/litespeed-vs-nginx-vs-apache-wordpress/) See also: LSCache HTTP/3 PHP-FPM and LSAPI ### LSCache Performance LSCache is the page cache built into the LiteSpeed server. Pages that have already been generated are served straight by the web server, without running PHP or querying the database. On WordPress, the free LiteSpeed Cache plugin drives it: automatic purge on every change, WooCommerce cart exclusions and an optional separate mobile cache. Also known as: LiteSpeed Cache Learn more: [LiteSpeed Cache Setup: Step-by-Step Settings for 2026](https://hosterwise.com/en/blog/litespeed-cache-setup/) [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) See also: Page cache Object cache QUIC.cloud ## M Back to the index ### MX record DNS and e-mail An MX (Mail Exchanger) record names the servers that receive a domain’s e-mail, each with a priority: the server with the lowest number is tried first. Without a correct MX record, messages sent to hello@your-domain.com cannot be delivered. Also known as: MX, MX records See also: SPF DKIM DMARC ## N Back to the index ### Name server DNS and e-mail A name server hosts a domain’s DNS zone and answers queries about it. A domain’s name servers are declared to the registry by the registrar: changing them hands the whole DNS management over to another provider, for example during a migration. Also known as: name servers, nameserver, nameservers, DNS servers Learn more: [Domain names](https://hosterwise.com/en/domain-names/) [Free migration](https://hosterwise.com/en/free-migration/) See also: DNS Registrar DNS propagation ## O Back to the index ### Object cache Performance An object cache keeps the results of WordPress database queries in memory so they can be reused from one page to the next. It relies on Redis, Memcached or LSMCD and mostly speeds up pages that cannot be page-cached: the cart, the customer area and the dashboard. Hosterwise provides a Redis object cache on every plan. Also known as: object caching, Redis, Memcached, LSMCD Learn more: [WooCommerce hosting](https://hosterwise.com/en/woocommerce-hosting/) [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: Page cache OPcache ### OPcache Performance OPcache is a PHP extension that keeps already compiled PHP code (bytecode) in memory. Without it, every request would read and compile the files of WordPress and its plugins all over again. Bundled with PHP since version 5.5, it noticeably cuts page execution time and CPU load. Also known as: Zend OPcache Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: PHP-FPM and LSAPI Object cache ## P Back to the index ### Page cache Performance A page cache stores the complete HTML of a page after it is first generated, then sends it as-is to the next visitors without running PHP or querying the database. It is the single most effective speed-up for WordPress. It can be handled by the web server, like LSCache on LiteSpeed, or by a plugin. Also known as: page caching, full-page cache Learn more: [Speed Up WordPress: 15 Practical Actions That Work](https://hosterwise.com/en/blog/speed-up-wordpress/) [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) See also: LSCache Object cache TTFB ### Permalink WordPress A permalink is the permanent address of a post or page. WordPress lets you pick its structure under Settings → Permalinks; the “Post name” structure (/%postname%/) gives short, readable URLs. Changing the structure of an existing site means redirecting the old addresses with 301s. Also known as: permalinks Learn more: [How to Migrate a WordPress Site With Zero Downtime](https://hosterwise.com/en/blog/migrate-wordpress-site/) See also: 301 redirect ### PHP-FPM and LSAPI Servers and hosting PHP-FPM (FastCGI Process Manager) is the most common PHP process manager alongside Nginx and Apache: it keeps a pool of processes ready to run the PHP code of your pages. LiteSpeed servers use their own equivalent, LSAPI, a PHP interface built for LiteSpeed that does the same job. Also known as: PHP-FPM, LSAPI, LSPHP Learn more: [LiteSpeed vs Nginx vs Apache: Which Web Server for WordPress?](https://hosterwise.com/en/blog/litespeed-vs-nginx-vs-apache-wordpress/) [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) See also: OPcache LiteSpeed ### Point of presence (PoP) Performance A point of presence (PoP) is a physical location where a CDN runs servers, as close as possible to the internet users of a region. Visitors are routed to the nearest PoP, which serves them the cached copy of the page: less distance, so less latency. The QUIC.cloud network had 78 PoPs on 12 October 2026. Also known as: PoP, points of presence Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: CDN Reverse proxy TTFB ## Q Back to the index ### QUIC Performance QUIC is a transport protocol first designed by Google and standardised by the IETF in 2021 (RFC 9000). It runs over UDP, builds in TLS 1.3 encryption and carries each data stream independently of the others. It is the foundation of HTTP/3 and mostly improves mobile or unstable connections. Learn more: [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) See also: HTTP/3 SSL/TLS ### QUIC.cloud Performance QUIC.cloud is the CDN run by LiteSpeed Technologies. Placed as a reverse proxy in front of the server, it caches WordPress pages and static files in its points of presence (78 on 12 October 2026), purges them through the LiteSpeed Cache plugin and speaks HTTP/3 end to end. At Hosterwise it serves every site, on every plan. Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) See also: CDN Reverse proxy LSCache ## R Back to the index ### RDAP Domain names RDAP (Registration Data Access Protocol) is the standardised successor of WHOIS. It returns a domain’s registration data in a structured format (JSON) over HTTPS and can tailor what is shown to who is asking. For generic extensions, ICANN made it the authoritative source in place of WHOIS on 28 January 2025. Also known as: Registration Data Access Protocol Learn more: [Domain names](https://hosterwise.com/en/domain-names/) See also: WHOIS ### Registrar Domain names A registrar is the company you book a domain name through. Accredited by the extension’s registry, and by ICANN for generic extensions, it passes your details to the registry and handles renewals and name servers. At Hosterwise, you register and renew your domains alongside your hosting. Also known as: domain registrar Learn more: [Domain names](https://hosterwise.com/en/domain-names/) See also: Registry EPP code WHOIS ### Registry Domain names A registry is the organisation that runs a domain extension: it keeps the database of registered names, sets the allocation rules and operates the extension’s DNS servers. Afnic runs .fr, Verisign runs .com and .net, and EURid runs .eu. To register a name you go through a registrar. Also known as: domain registry Learn more: [Domain names](https://hosterwise.com/en/domain-names/) [.fr domain name](https://hosterwise.com/en/domain-names/fr/) See also: Registrar Domain extension (TLD) ### Reverse proxy Performance A reverse proxy is a server placed in front of a site’s origin server: it receives visitors’ requests, answers them itself when it holds an up-to-date copy of the page and passes the rest on to the origin. It is used for caching, load balancing and traffic filtering. A CDN is a reverse proxy spread across the world. Also known as: reverse-proxy Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: CDN QUIC.cloud Point of presence (PoP) ## S Back to the index ### Shared hosting Servers and hosting Shared hosting puts several sites on the same server, whose resources (CPU, memory, disk) are shared and managed by the host. It is the most affordable and simplest option: server security and updates are handled for you. In return, the resources allocated to each account are capped. Also known as: shared web hosting Learn more: [Pricing](https://hosterwise.com/en/pricing/) See also: VPS Cloud hosting Control panel ### SLA Servers and hosting An SLA (Service Level Agreement) is a host’s contractual commitment on service quality: availability rate, response times and the compensation due when the target is missed. A good SLA also states how availability is measured and what is excluded, such as scheduled maintenance. Also known as: Service Level Agreement, service level agreement Learn more: [Service level agreement (SLA)](https://hosterwise.com/en/sla/) See also: Uptime ### SPF DNS and e-mail SPF (Sender Policy Framework) is a TXT record listing the servers allowed to send e-mail on behalf of your domain, for example “v=spf1 include:\_spf.google.com ~all”. Receiving servers check it to spot spoofing. A domain must publish only one SPF record. Also known as: Sender Policy Framework See also: DKIM DMARC TXT record ### SSH Servers and hosting SSH (Secure Shell) is a protocol that opens an encrypted command-line session on a server, used to run commands such as WP-CLI or to transfer files over SFTP. Hosterwise does not provide SSH access, as a security choice: everything is managed from CyberPanel, over FTP or from WordPress, and support runs any command you need. Also known as: Secure Shell, SSH access Learn more: [Frequently asked questions](https://hosterwise.com/en/faq/) See also: Control panel WAF (web application firewall) ### SSL/TLS Security SSL/TLS are the protocols that encrypt traffic between the browser and the server; SSL is the old name, and the versions in use today are TLS 1.2 and TLS 1.3. An SSL certificate vouches for the site’s identity and enables HTTPS, shown by the browser padlock. Hosterwise provides a free SSL certificate for each of your sites. Also known as: SSL certificate, SSL certificates, SSL, TLS Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: HTTPS Let’s Encrypt ### Staging site WordPress A staging site is a private copy of your website where you can test an update, a new plugin or a theme change without any risk to the live site. Once validated, the changes are pushed to production. It is the best protection against an update that breaks a site. Also known as: staging, staging environment See also: 3-2-1 backup WP-Cron ## T Back to the index ### TTFB Performance TTFB (Time To First Byte) measures the time between the browser sending a request and receiving the first byte of the response. It adds up DNS lookup, connection, TLS negotiation and page generation on the server. Google rates it good under 0.8 seconds, and a server-side cache such as LSCache cuts it sharply. Also known as: Time To First Byte, time to first byte, server response time Learn more: [LiteSpeed hosting](https://hosterwise.com/en/litespeed-hosting/) See also: Page cache CDN LCP ### TTL DNS and e-mail The TTL (Time To Live) of a DNS record says, in seconds, how long resolvers may cache the answer before asking again. A short TTL (300 seconds) makes changes visible faster; a long one (86,400 seconds, one day) cuts the number of lookups. Lower it before a migration. Also known as: Time To Live, time to live Learn more: [How to Migrate a WordPress Site With Zero Downtime](https://hosterwise.com/en/blog/migrate-wordpress-site/) [Free migration](https://hosterwise.com/en/free-migration/) See also: DNS DNS propagation ### Two-factor authentication (2FA) Security Two-factor authentication (2FA) adds a second proof of identity to the password, usually a temporary code from an authenticator app or a physical security key. Turned on for the WordPress dashboard and the hosting customer area, it stops most break-ins that rely on stolen or guessed passwords. Also known as: 2FA, two-factor authentication, two-step verification See also: WAF (web application firewall) ### TXT record DNS and e-mail A TXT record attaches free text to a domain name. It is mostly used to prove you own a domain to a service (Google Search Console, Bing Webmaster Tools, business e-mail) and to publish e-mail authentication rules: SPF, DKIM and DMARC are all published as TXT records. Also known as: TXT, TXT records See also: SPF DKIM DMARC ## U Back to the index ### Uptime Servers and hosting Uptime is the percentage of time a site or server responds normally. Over a 30-day month, 99.9% allows about 43 minutes of downtime and 99.99% about 4 minutes. It is tracked with an external monitoring probe and is often backed by a contractual commitment, the SLA. Also known as: availability rate Learn more: [Service level agreement (SLA)](https://hosterwise.com/en/sla/) [Frequently asked questions](https://hosterwise.com/en/faq/) See also: SLA ## V Back to the index ### VPS Servers and hosting A VPS (Virtual Private Server) is a virtual machine with reserved resources (CPU, memory, storage) on a shared physical server. It gives you full administrator access and plenty of freedom to configure it; in return, setting up, securing and updating the system is usually your job unless the plan is managed. Also known as: Virtual Private Server, virtual private server See also: Shared hosting Cloud hosting ## W Back to the index ### WAF (web application firewall) Security A WAF (Web Application Firewall) filters HTTP requests before they reach the site: it blocks SQL injection and cross-site scripting attempts, brute-force attacks on the login page and exploits of known plugin flaws. It can run on the server (ModSecurity), inside a plugin or at CDN level. Also known as: WAF, web application firewall, Web Application Firewall, ModSecurity Learn more: [Features](https://hosterwise.com/en/wordpress-hosting-features/) See also: Two-factor authentication (2FA) 3-2-1 backup ### WHOIS Domain names WHOIS is the long-standing lookup service for domain name information: registrar, creation and expiry dates, name servers and status. Since the GDPR, the personal details of individual registrants are usually hidden. It is gradually being replaced by the RDAP protocol. Also known as: Whois Learn more: [Domain names](https://hosterwise.com/en/domain-names/) See also: RDAP Registrar ### WP-Cron WordPress WP-Cron is the WordPress task scheduler: it publishes scheduled posts, checks for updates, sends e-mails and runs plugin jobs. It does not run continuously but fires when people visit the site. On a low-traffic site it is better to disable it and trigger it with a real server cron job. Also known as: WP Cron, WordPress cron, wp-cron.php See also: Staging site ## Ready to put it into practice? LiteSpeed, LSCache, HTTP/3, the QUIC.cloud CDN, SSL and backups come ready-configured on our WordPress plans, from 6,99 €/month. [See the plans](https://hosterwise.com/en/pricing/) [All blog articles](https://hosterwise.com/en/blog/) 30-day money-back guarantee --- Markdown version of , generated by Hosterwise. Site index for AI assistants: