Navigating the Terminal

The ~ character is known as a Tilde (pronounced like milled but with a T). ~ is used as short hand for your home directory.

~/ is therefor the same as navigating to your home folder in the finder or pressing Cmd + Shift + H.

Since your desktop is located in the home folder, the path is ~/Desktop

using the cd command we can navigate to the desktop using Terminal.

write or copy and paste cd ~/Desktop into the Terminal and hit return. Entered correctly, you will be prompted with user:Desktop user$ (user being replaced with your user name). 

We have now successfully navigated to the Desktop within Terminal.