Identical means exactly the same in every way. When two things are identical, you can't find any difference between them, no matter how closely you look. Identical twins come from the same fertilized egg and share almost the same DNA, and they often look so much alike that even their parents sometimes mix them up. Two identical snowflakes would have the exact same pattern in every tiny ice crystal, though in reality, no two snowflakes are truly identical.

If you printed two identical copies of an essay, every word, comma, and space would match perfectly. If someone commits a crime and police find their fingerprints at two scenes, those identical prints show the same person was at both places.

People sometimes confuse identical with similar, but they're different. Similar things resemble each other but aren't exactly the same. Your backpack might be similar to your friend's (same brand, same size), but identical backpacks would be impossibly hard to tell apart. When a judge demands the identical wording in a contract, she wants every single letter to match, not just the general idea.