What is HTTP/2 and does it different from HTTP/1.1?

Sir Timothy John Berners-Lee invented the HTTP protocol in 1989 on a NeXTcube workstation with 25 MHz CPU and several MBs of RAM. That worked on networks with port connection speeds of 10 Mbits.

But now, we have dramatically faster CPUs and thousands of MBs of RAM. So, we need protocol speed to upload the web pages faster. And HTTP/2 is here to solve that issue.

In 2015, however, the Internet Engineering Task Force (IETF) released HTTP/2, the second major version of the most useful internet protocol, HTTP.

Let's get more information about HTTP/2, and will know how it differs from HTTP/1.1.

Hypertext Transfer Protocol (HTTP) is a set of standards allowing internet users to exchange website information. HTTP/2 was released in 2015 as a major revision to the HTTP/1.1 protocol. It was derived from the SPDY protocol as a way to improve the online experience by speeding up page loads and reducing round-trip time (RTT), especially on resource-heavy web pages. HTTP/2 was developed by the Hypertext Transfer Protocol working group httpbis (where bis mean "second") of the Internet Engineering Task Force.

In 2010, Google released the SPDY protocol as a way of modifying how HTTP handles requests and responses. Its focus was on reducing latency via TCP pipelining and providing mandatory compression, amongst other features.

While HTTP/2 was initially modeled after SPDY, it was soon modified to include unique features, including a fixed header compression algorithm.

How is HTTP/2 different from HTTP/1.1?

HTTP/1.1 was the third version of HTTP and the standard protocol for over 15 years. After a few years, it started to show its limitations. Specifically, its use of one outstanding request per TCP connection created significant overhead, slowing down page load times.
HTTP/2 is binary, instead of textual.
HTTP/2 improved on HTTP/1.1 in a number of ways that allowed for speedier content delivery and improved the user experience.
Web browsers only support HTTP/2 via encrypted connections, increasing user and application security.
HTTP/2 uses header compression to reduce the overhead caused by TCP’s slow-start mechanism.
HTTP/2 is multiplexed, i.e., it can initiate multiple requests in parallel over a single TCP connection. As a result, web pages containing several elements are delivered over one TCP connection. These capabilities solve the head-of-line blocking problem in HTTP/1.1, in which a packet at the front of the line blocks others from being transmitted.
HTTP/2 servers push likely-to-be-used resources into a browser’s cache, even before they’re requested. It allows browsers to display content without additional request cycles.
HTTP/2 can handle elements betterly such as whitespace, capitalization and line endings.
Google upgrading to the HTTP/2 imperative for online businesses wishing to reduce RTT and speed up page load times.
The new extension to Transport Layer Security (TLS) means a site must first be HTTPS compatible to use HTTP/2.
HTTP/2 requires your developers and designers to come up with new solutions to overcome HTTP/1.1 bugs.
HTTP/2 has good performance characteristics for HTTP “APIs” because the APIs don’t need to consider things like request overhead in their design.
HTTP/2 is supported by the most current releases of Edge, Safari, Firefox, and Chrome. Other browsers based upon Blink will also support HTTP/2 (e.g., Opera and Yandex Browser).