vim add character at the beginning of all lines code example

Example: vim insert text at the the beginning of multiple lines

# Basic syntax:
# Insert text in front of every line in the file:
:%s!^!text_to_insert!

# Insert text in front of specific lines (e.g. for commenting out code):
1. Press ESC to ensure youre in command mode
2. Use CTRL+v to enter visual block mode
3. Move Up / Down to select the rows you want to prepend text to
4. Press SHIFT+i and type the text you want to insert (it will only
	show up on the current row for now)
5. Press ESC, wait ~1 second and the inserted text will appear on
	every line