Progressive Web Apps brings native apps features to the web. Leveraging Service Workers, offline modus, a manifest and (background) push notifications are made available.
Recently also announced support for Safari.
HTTP/2 is a (complex) successor to the existing decades old http protocol. The complexity is caused by its binary format (compared to the existing text) but that is also its strong point for a faster web experience.
HTTP/2 enforces SSL and allows webservers to pre-load certain content in the user's browser.
WebRTC provides (mobile) browsers Real-Time Communications (RTC) capabilities.
Service Workers allow background processes in the browser, offline experiences, advanced caching, and push notifications. See also Progressive Web Apps.
WebAssembly brings binary compilation, and multithreading to the browser.
Web Components brings Custom Elements, Shadow DOM and HTML Imports together to allow for a native modular web development environment.
Content Security Policy (CSP)