How do I save all files (or save all buffers) in Emacs?

Question

C-x C-s saves only the current buffer.

How do I save all files (or all buffers)?

Answer 1

Press "C-x s" and then choose "!" for saving all buffers.

Answer 2

Another way might be using list-buffers

1. C-x C-b RET ; 3rd column shows '*' for modified buffers.
2. s ; Mark the buffer at point to be saved.
3. x ; Save and/or delete marked buffers.

With ibuffer is slightly different:

1. M-x ibuffer RET ; 2nd column shows '*' for modified buffers.
2. m ; Mark the buffer at point.
3. S ; Save the marked buffers.