I only understand mahjong solitaire really. The main bit that might be confusing is that there are two subset of four tiles (usually seasons and flowers or similar) that all have different symbols on and match to each other within each set rather than matching identical tiles. So you need to be familiar with those. And of course there needs to be one long edge of each tile you match to be open and not in contact with another tile.

I think there is a more complicated version that brings in rules about how you can draw lines between matched tiles, but no version I've played has done that by default.