Generally, every pronoun can be shortened to only three or four letters. For example, Bapak to Pak, Ibu to Bu, etc. Names can also follow such unwritten rules. Budi shortened to Bud, Michael to Mic/Mike, Iqbal to Bal, Bintang to Bin or Tang, etc. My name, Daffa, can be shortened to Daf, or more commonly, Dap.

Another unwritten rule people would often follow is the substiution of letters, mainly the letters F and P. Using the previous example of Daf, Indonesians would often switch out the F for the P, thus saying Dap.