How can Vim stop responding?

session, terminal, vim

Solution

You've stopped the terminal with `CTRL-S`. To resume, press `CTRL-Q`. Btw, this is not VIM-specific, but rather terminal-specific.

Problem

With an intention to increment a number in a line in Vim, I pressed Ctrl+A. To my wonder Vim stopped responding! Later I realized that I had actually pressed Ctrl+S. Can somebody please explain this behavior? I've made some changes to the file, but not saved before vim stopped responding. (Aside: Ctrl+X decreases the next number on the line)

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