What are pointers in Go and how are they used?

Pointers in Go: • Store memory addresses of variables • Use & to get address, * to dereference • No pointer arithmetic (unlike C) • Zero value is nil • Useful for efficiency and modification Example: var x int = 42 var p *int = &x // p points to x fmt.Println(*p) // prints 42 *p = 21 // changes x to 21 func modify(p *int) { *p = 100 }