Acronym for Hypertext Markup Language. Markup meaning that there are tags which explain the role of each piece of content. Hypertext indicates that HTML goes beyond mere text thanks to its system of linking to other texts (or HTML pages) and so, builds a hyper-structure that binds websites around the world. And no, it's not a programming language.

The current version is HTML5, which was preceeded by XHTML, which was not scrictly-speaking HTML, but XML. XHTML was, nevertheless, considered the successor of HTML4 for a while.

HTML5 was born to simplify everything by going straight to the point. Moreover, more tags were added to allow greater semantic markup capabilities.

Cascading Style Sheets is a language to define styles. While the purpose of HTML is defining a role for each piece of content, the purpose of CSS is to tell how this content should be visually presented.

Initially, only pure visual aspects were described, but since version 3 a lot of functionality was added, providing features that previously were only possible using JavaScript.

Often preprocessors like Sass or Less are used to generate source code more efficiently and make it easier to maintain.

This is the programming language every browser understands. Today most websites use this technology to enhace user experience.

Libraries and frameworks, such as jQuery, React, Angular or Vue.js, can extend the language.

But ... is there anybody not using JavaScript? Yes, indeed: web developers testing whether the website works fine without JavaScript and paranoid users in dark networks who consider that JavaScript is a gateway for attacks against their privacy.

A superset of JavaScript to make it static typed (that is, to define for each var whether it is an integers, a string, an objects, etc.). Static typing helps reduce runtime errors.

It was first used in Angular, but it can also be used with React, Vue or just instead of plain old JavaScript.

When used on the web, TypeScript code ends up transcompiled into JavaScript code, which any browser can understand.

React is a JavaScript library (almost a framework) maintained by Facebook that helps us in building interactive content. It can either extend traditional multipage web functionality or build single-page applications (SPA).

It can be used to develop mobile applications in combination with other libraries.

Being one of the most popular JavaScript libraries, many resources can be found for almost any desired feature, either as a plugin or as help from other developers.

Vue is a JavaScript framework, similar to Angular but simplified and lighter. In fact, it was created by a former Angular developer.

Like Angular, it can be used to build single-page applications (SPA), but its light weight makes it very convenient for simpler tasks such as controlling interactive parts in a multiple page application (MPA).

It's not maintained by any big company, but there is a big and growing community providing enough resouces for any kind of project.

Just like its competitors React and Angular, Vue.js is also suited for building mobile applications, although some options have still limited support.

A JavaScript library. In its golden age (about eight years ago) it was almost a de facto standard on websites.

It allows covering every common browser without having to write duplicated code to account for differences, as well as simplifying many tasks. Hence its slogan "Write less, do more". It also provided a simple way to do animated transitions when CSS3 wasn't fully supported.

Its use has been falling out of favor since many of the older, most problematic browsers, have been progressively abandonded (mostly old versions of Microsoft's Internet Explorer). Moreover, the use of transpilers and polyfills help cover those old browsers whilst allowing to write in modern JavaScript and using its latest features.

Other libraries and frameworks such as React, Angular and Vue.js have also contributed to its decline, although they are not perfect replacements and sometimes jQuery is still used in combination with them.

HTTPS stands for HTTP over SSL. SSL stands for Secure Socket Layer and it is an encrypted channel to transmit information in a way that it can't be intercepted. Actually, SSL is an old protocol and today TLS (Transport Layer Security) is recommended instead, but often SSL refers to both SSL and TLS.

To use HTTPS we have to install a certificate on the server that gets renewed each year and adapt the website to the new URL. Basic certificates are free and convenient in most cases, but the initial installation and certificate renewal service is often charged. Most hosting plans include this service with no extra cost.

Having your website over HTTPS enures that it hasn't been suplanted and communications cannot be peeked by a third party. As an extra, browsers stating that our site is secure gives visitors more confidence and a better impression about our business.

These secure channels are also used by electronic mail applications to connect to the server, but there's no need to provide a certificate because mail servers are usually managed by hosting provider, which will have installed its own certificate (if not, it might be time to change provider!). For security reasons it is best to connect to IMAP and SMTP servers with SSL or STARTTLS activated.

A language designed to be run in browsers and created by taking the best parts of different languages (C, C++, Rust, Java). "It comes to obliterate JavaScript", says many a JavaScript hater.

Currently supported by all popular browsers, it is probable that it will soon be used instead of JavaScript in some cases, but a complete substitution is not likely to happen. JavaScript works fine and is resonably efficient in most cases.

WASM can indeed be a good complement for JavaScript, specially in parts requiring high-performance operations, but it is still not ready for production environments.

As any database, it allows data storage, but unlike relational ones information is not stored in tables and there is no information on which type of data is going to be stored. So, basically, you can store anything on the fly. Just as with SQLite, it can be integrated in applications.

A common example is MongoDB, consisting of serveral collecions of JSON documents.

Restrictions are often defined in the application, to compensate for the lack of restriction in the database. There are libraries like Mongoose for that purpose.

Another example is IndexedDB, a database available in modern browsers.

WAI is an initiative to make websites accessible to all. It was born to promote the use of coding practices that would allow people with different accessibility needs the use of websites with special devices.

Inside WAI, there are the WCAG, web content accessibility guielines. The WCAG tell us how to make websites accessible. E.g. each image must have a descriptive text for its interpretation in non visual contexts.

In addition, following these guidelines is an excellent way of optimizing the web for search engines (SEO).

A late-comer is WAI-ARIA. Standing for Web Accessibility Initiative - Accessible Rich Internet Applications, it takes accessibility one step further to include dynamic content and user interface components, such as forms.

The names comes from Asynchronous JavaScript And XML. It's a collection of practices with JavaScript for a website to interact with the server without having to refresh the page. It allows for the dynamic load of more data (for instance, extra content when scrolling down) or to send data asynchronously, while the app keeps performing other tasks.

In the beginning, the XML language was used to fetch data from the server, but nowadays JSON or even HTML are also quite common.