The empty interface interface{} (or any) holds values of any type by having no required methods.
The empty interface interface{} (or any in Go 1.18+) is a type that holds values of any type because it has no methods to satisfy. Use it when you need a variable to store data of unknown or varying types, such as in generic collections before generics were available.
var v interface{} = 42
v = "hello"
v = []int{1, 2, 3}
// Go 1.18+ alias
var a any = v
The empty interface is like a universal box that can hold anything, from numbers to text to complex objects. You use it when you don't know exactly what kind of data you will receive or need to store mixed types together. Think of it as a generic container that accepts any item without checking what it is.