Macros are sequences of commands in Vim that can be recorded to build up more complex tasks and then run them again.
Record a vim macro
This will put you in a mode where you'll be recording your commands as they run until later, when you say to stop recording.
q - start the recording.
a-z - store the macro in a register (ie, any letter a to z) for later recall.
Add commands to macro
Then you start typing commands in a way that's repeatable. These can be any normal commands! They might include:
0 - start at the beginning of the line.
fX - move next instance of a certain character (eg, "X").
r' - replace some character with another (eg, "'").
bp - paste from a register (eg, "b").
j - go the next line.
q - stop the recording.
Run a vim macro
After you've recorded a macro, you can use it as long as it stays recorded. (Be careful not to overwrite any you want to keep.)
0-9 - (optional) the number of times you want to run the macro.
@ - indicate you're going to run the macro.
a-z - the register in which you previously stored your macro.
Run the last macro again
@@ - whichever was run last will be run again
See what macros are in your registers
If you ever forget what you have recorded, you can list them. The hard part is reading what you've recorded. :)
:reg - list contents of all registers
Any other tips on running macros in vim?