Into is a word that shows movement or change from outside to inside, or from one state to another.

When you walk into a room, you move from the hallway to the space inside. When you dive into a pool, you go from being on the deck to being in the water. When you look into someone's eyes, your gaze goes from the outside world to focusing on that person.

The word also describes transformation or becoming deeply involved with something. When you get into a good book, you become absorbed in the story. When water freezes, it turns into ice. When someone gets into trouble, they've moved from being fine to having a problem. A caterpillar transforms into a butterfly. When you're really into soccer or piano, you're deeply interested and engaged.

You can also divide or break things into parts: cutting a pizza into eight slices, or splitting your class into four teams. The word shows how one whole thing becomes multiple pieces.

Into is different from in to, which is two separate words. You might go in to check on someone (where in describes where you go, and to shows purpose), but you walk into a room (where into shows the movement itself).