My terminal is broken!

Can you still type commands?

 

Likely you edited a file such as .profile or .bash_profile, or you installed an application that did. These are hidden files inside your home directory (not everyone has them) so you will not be able to see them from Finder unless you have turned the visibility of hidden files one. Turning them on can be done with TinkerTool. It could also be done with Terminal, but that's currently decommissioned.

Once you can see the file(s) you can open them in a text editor and fix what you changed, or if there's nothing important in them, just delete the files. Some text editors (like TextWrangler) can open hidden files from their interface so you don't have to worry about messing with the above app.

 

When Terminal is running, go to your menu bar and pick Shell->New Window->Basic. See if you get anything beyond the blinking cursor you normally see in your current default "homebrew" themed terminal. If it works, then go back to terminal preferences and make basic your default for new terminal windows and you should never have to stare at the blinking green thing again.

Now if you cannot get any text into terminal in any of its themes you might have a more serious problem. Let's hope this is simply a matter of a munged theme (homebrew).

 

Try restarting.

 

Seconding Angelwatt here. Easiest way to reset them is to create a new user account on the machine and copy them over from one account to the other, being sure to change ownership on the files.

 

beat me to it... you would be shocked at the number of computer problems that can be fixed by reboot.

 

Rebooting as the first solution to fix problems should be a sticky.