The CSS display property has been upgraded to a two-valued syntax. This will allow us to make new layouts that were not possible before.

The new CSS properties such as text-decoration-thickness, text-decoration-color etc can help in creating attractive text decorations and underlines, which were not possible before.

Variable fonts is a new font technology that allows a single font file to store multiple variations of the font. Variable fonts are going to bring a major change in web design.

Many next generation CSS properties and APIs have been introduced in browsers lately. These can help in creation of user interfaces that were previously not possible or were difficult to achieve.

If Javascript code executed on the main thread could be offloaded to several Web Workers, then performance problem of a web application would be solved almost completely.

Performance of the 〈canvas〉element can be greatly improved using the newly introduced OffscreenCanvas. This can offload canvas logic and rendering to a background process rather on the main browser thread.

Many HTTP headers have been newly introduced like Content-Security-Policy, Feature-Policy etc. These new headers can make your application secure and boost its performance.

This video will show how browsers handles white space characters in HTML (word space, tab, carriage-return, line break) and how it can be controlled with CSS properties.

This video offers an introduction to CSS Grid. It can be used to create responsive user interfaces by dividing the web page into a grid of rows and columns.

Data immutability becomes important when there are several developers working on a huge web application. This video shows how you can create immutable objects in Javascript.

CSS variables makes many UI problems easy, which were not straightforward before. This video will show you many interesting details about CSS variables.

Web development is entering to a totally new phase with WebAssembly coming in. With WebAssembly it is possible to run desktop like applications inside a browser.

WebVR APIs aims at making VR and AR more accessible. All VR headsets shall be supporting WebVR and the user can view the VR experience in the same webpage which he is browsing.

The WebUSB API allows USB devices and the browser to communicate with each other. With this you can build hardware for the web.

Good typography does not improve speed or understanding, but leads to greater engagement in reading. This video presented at CSS Day brings out some general guidelines for typography on websites.

The Javascript event loop is the key to understanding terms such as "Asynchronous", "Single-Threaded", "Non-Blocking" etc. This is explained through a video presented at JSConf.