The above displays your User Agent (UA) String of the browser you are using.
What Is A User Agent?
When you visit a website, your internet browser provides information to the website about your browser, operating system, device, screen resolution, and more. When communicating with websites in this way on behalf of the user, the browser is acting as a user agent.
The purpose of UAs is to allow servers and network peers such as websites to identify information about the user, including application, operating system, browser and browser version, and more. This allows websites to optimize the browsing experience for users across all browsers and operating systems.
For example, websites that can detect UA information can redirect mobile users to the mobile version of the website. Not all sites have UA detection in place - that's one reason why some websites look bad on mobile.
In a user agent string, the most important information is provided first. Most user agent strings look something like this:
Mozilla/[version] ([system and browser information]) [platform] ([platform details]) [extensions]
So, a user on a Windows 10 computer using Google Chrome will have a user-agent that looks similar to this:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.81 Safari/537.36
Can You Change Your User Agent?
Web developers often use user agent switchers or user agent managers to change their UA to see how their websites look and perform with different browsers and devices. This is often referred to as user-agent spoofing.
Some privacy-focused internet users also change their UA in order not to be tracked online by websites and ad bots.
How To Change Your User Agent
Because each browser is unique, each has a unique code that appears in the browser as the default user agent string. For example, the Chrome user agent is different than the Firefox user agent. Chrome, Edge, and Safari have browser-supported built-in tools that allow you to change your UA. With Firefox, you’ll have to use an add-on called User-Agent Switcher.
With any of these methods, you will be able to change your UA to mask yourself as using a different browser, browser version, operating system, screen resolution, etc. Again, this is very useful when testing how websites will perform in various situations.
If you’re not a web developer and simply want more privacy when browsing the internet, there is another option. You can use a random user-agent, which replaces your UA string with a different, random UA string after a specified period of time.