Wget is a linux application for downloading anything. You can download websites, files, directories and even bypass robots.txt if you want to.
With wget you can download any file in linux using wget filename.url
Its as easy as that, if you want to download a website you can use wget website.com
Those are the two really easy methods of downloading something but once you learn more commands wget becomes a very powerful downloading tool which you can use to even mirror entire websites.
The first command you can use is m
for example wget -m wikipedia.org
That will download the entire wikipedia, the m in the command stands for -mirror, you can also use –mirror instead of m.
-A This is a command to download something specific of a website or a certain type of file for instance wget -a