Blot techniques

NoRthern blot is for RNA. The opposite, Southern blot is for DNA.
So what remains is the Western - for proteins.

Here's a more effective mnemonic if you know about Indian food habits.
In North India  Roti is favourite food - Northern RNA
South India : Dosa - Southern DNA
Western world food : Pizza - Western Proteins

For Hindi knowing people, here's an alternate menmonic:
South = Dakshin - DNA
West = Paschim - Proteins