"Się" is a part of a reflexive verb. There is a really good analogy in Spanish - I can see that you know some Spanish, so maybe it will be helpful for you: Let's take an example of reflexive verb in Spanish: LLAMARSE the ending changes because of the conjugation: -me, -te, -se... The concept is simmilar here - there are only two differences: in Polish we write it separately and it never changes - it remains "się" for every person. Nazywam się - My name is...//Me llamo Nazywasz się - Your name is..//Te llamas Nazywa się - His/her name is...//Se llama etc. There is also an English analogy for that: He hurt himself while cutting meat. --> Zranił (verb) się (reflexive part) krojąc mięso. But that analogy is not as acurate as the Spanish one, because it doesn't apply in most of the cases, because in English you don't have that much "reflexiveness" to verbs ;) I hope it will help :)