How are data structures represented in object-oriented programming and where are they used?

In object-oriented programming (OOP), data structures are usually represented by classes or structures (structs), which combine data and methods for working with them. In Go, for example, structures (struct) are used to create custom data types that can contain fields of different types.

Data structures are used to organize and store data in a convenient form for processing. They are used everywhere where related data needs to be stored, such as describing entities of a subject area (user, order, point on a plane, etc.).

Example of a structure in Go:

package main
import "fmt"

type User struct {
    ID   int
    Name string

    Age  int
}

func main() {
    u := User{ID: 1, Name: "Ivan", Age: 30}
    fmt.Println(u)
}

Here, User is a structure that combines several fields describing a user. Such structures can be used for passing data between functions, storing in slices, maps, etc.