Original: Though the word proselytism originally referred to Early Christianity (and earlier Gentiles), it also refers to other religions' attempts to convert people to their beliefs or even any attempt to convert people to another point of view, religious or not.
Simplified: Though the word proselytism was originally used in Christianity, it is also used to refer to other religions' attempts to convert people to their beliefs or even any attempt to convert people to another point of view, religious or not.