The anatomy of a download over TCP
Let's look at what happens from download instantiation by some download client to when all data in its completeness is transferred from the remote location to the downloader's storage.
Getting a uri to a remote resource
You have been given some link of the form
http://somesite.com:8031/file.txt to a remote file. From the URL we
can tell the remote file is located at the root folder / on the
hosting server and that it is called file.txt. This website is on some
server that supports the http protocol. Its hosted somewhere off your
system accessible via a network.