How does the brain remember things?

Your brain remembers by linking groups of neurons into patterns. A new experience first makes a temporary pattern, and practice or importance can strengthen the links until the memory lasts. When you recall it, your brain re-creates the pattern rather than opening a stored copy.

One especially nice detail is that sleep helps sort the day. While a child is tucked up, the hippocampus helps recent experiences become steadier in the cortex. Big feelings can also make a memory cling harder, which is why a funny spill may outlast an ordinary breakfast.