How to check Internet speed from the command line on Linux

If you are trying to check Internet speed from a remote headless server, VPS or an otherwise desktop-less system, Speedtest.net’s Flash-based user-friendly interface would be no good. For those of you, there is a command-line interface (CLI) version of Speedtest.net, known as speedtest-cli. Here I will demonstrate how to use speedtest-cli to check Internet speed from the command line in Linux.