Problem:

It happened to me a number of times. Usually, I am habitual of using Ctrl+S to save a text editor like Word, Gedit etc. What goes wrong is when I am editing in command line editor such as Vi and I press Ctrl+S or if I accidently press this combination of key. Because it makes the terminal dead, frozen, hanged.

Reason:

Using Ctrl+S in Linux terminal locks the terminal output and it seems as if the terminal is frozen or hanged. It frustrates the most when it happens for the first time and user is simply unaware of the fact that he has accidently locked the terminal output.

Solution:

To unlock the terminal output use Ctrl+Q. It will resume the terminal output and put it back to normal.

Hope it helped you. Cheers