Main, Tum, Aap: Choosing the Right You
Launch library · evergreen read

Hindi has three common words for you, each carrying a different level of familiarity and respect: तू (tu), extremely intimate and rarely used outside very close relationships, तुम (tum), casual and friendly, and आप (aap), respectful and formal. Choosing the wrong one can sound either coldly distant or oddly overfamiliar.
So most learners are advised to default to aap until a relationship clearly signals otherwise. Native speakers rarely mind a learner erring on the side of formality. Learning main, I, tum and aap early, along with the verb forms each requires, gives a learner the pronoun foundation needed for almost every other sentence pattern in Hindi grammar that follows.
Learners should not feel embarrassed asking a Hindi speaking friend directly which pronoun feels most comfortable for them to be addressed with. Preferences can vary by personality as much as by relationship, and asking shows genuine care about getting the tone right rather than guessing and potentially causing quiet discomfort.