Windows 10:

Edge Browser (Preinstalled on Windows 10)

Google Chrome 

Firefox

Windows 7 and Windows 8/8.1

Internet Explorer 11 (Preinstalled on Windows 7 and 8/8.1)

Google Chrome 

Firefox

Windows XP:

(WIndows XP is no longer supported from Microsoft. Most modern webrowsers will no longer work for it.)

In case you still need a pdf reader you can download and install Adobe Acrobat Reader DC.

MacOS:

Safari (Already preinstalled on MacOS devices.)

Linux:

Google Chrome 

Firefox

Android: 

Google Chrome

IOS:

Safair (Already built into modern versions of IOS.)