Go Slices: Why Your Function Isn't Changing What You Think It Is

This beginner-friendly article explains why modifying a slice inside a Go function sometimes reflects in the caller and sometimes doesn't. It uses a 'sticky note' mental model to show that a slice header (pointer, length, capacity) is copied by value, so element mutations are visible but append changes are not unless a pointer is passed. It also covers deep cloning with copy() for full isolation.