I use Remmina because I like its minimal, easy-to-use user interface (UI).
These connections are made using remote desktop connection software, and there are many options available. Remote desktops are also used to help customers solve computer problems: with the customer's permission, you can establish a VNC or Remote Desktop Protocol (RDP) connection to see or interactively access the computer to troubleshoot or repair the problem. For example, the ManageIQ/Integration tests repository's pull request (PR) testing system exposes a Virtual Network Computing (VNC) connection port so I can remotely view my PRs being tested in real time. In other words, a remote desktop is used to access an environment running on another computer.
A remote desktop, according to Wikipedia, is 'a software or operating system feature that allows a personal computer's desktop environment to be run remotely on one system (usually a PC, but the concept applies equally to a server), while being displayed on a separate client device.'