[Pointers Video](https://youtu.be/MhQw9FNWVMQ) A pointer is a variable that stores the _memory address_ of another variable. This means that a pointer "points to" the _location_ of where the data is stored _NOT_ the actual data itself. The `*` syntax defines a pointer: ```go var p *int ``` The `&` operator generates a pointer to its operand. ```go myString := "hello" myStringPtr := &myString ``` Pointers allow us to manipulate data in memory directly, without making copies or duplicating data. This can make programs more efficient and allow us to do things that would be difficult or impossible without them. The `*` dereferences a pointer to gain access to the value ```go fmt.Println(*myStringPtr) // read myString through the pointer *myStringPtr = "world" // set myString through the pointer ``` Pointers can be very dangerous. If a pointer points to nothing (the zero value of the pointer type) then dereferencing it will cause a runtime error (a [panic](https://gobyexample.com/panic)) that crashes the program. Generally speaking, whenever you're dealing with pointers you should check if it's `nil` before trying to dereference it. #### POINTER RECEIVERS A receiver type on a method can be a pointer. Methods with pointer receivers can modify the value to which the receiver points. Since methods often need to modify their receiver, pointer receivers are _more common_ than value receivers. However, methods with pointer receivers don't require that a pointer is used to call the method. The pointer will automatically be derived from the value. ##### Pointer Receiver ```go type car struct { color string } func (c *car) setColor(color string) { c.color = color } func main() { c := car{ color: "white", } c.setColor("blue") fmt.Println(c.color) // prints "blue" } ``` ##### Non-Pointer Receiver ```go type car struct { color string } func (c car) setColor(color string) { c.color = color } func main() { c := car{ color: "white", } c.setColor("blue") fmt.Println(c.color) // prints "white" } ```