Software applications developed by a person or a company rather than the original manufacturer or the owner of the website that offers it is called third-party apps.
In short, the Internet was not a single person's hard work; instead, it was a brainchild of many scientists over a couple of decades.
Cache, aka web cache is a temporary storage location in the computer for storing the files that are downloaded by the browser. These files tend to take a lot of space in memory and are generally unnecessary.
Defrag, short for Defragging, refers to the maintenance task that shifts the position or the layout of the files on the hard drive. For faster access, drives should get defragmented regularly.
‘Private Browsing' is a unique optional feature built into web browsers, that makes sure Browsing History is not stored and Cookies are not saved. Once enabled, this ensures that one does not leave any trace with the browser.
Platform-as-a-Service, abbreviated as PaaS, is a type of cloud computing model describing the concept of delivering a computing platform as an integrated solution or service over an internet connection.