In what cases is a data structure with the ability to store sequential elements and their dynamic modification used?

Data structures that allow storing sequential elements and dynamically modifying them are used in cases where the size of the data is unknown in advance or when frequent addition, removal, or modification of elements is required without reallocating the entire structure.

Examples of such structures are slices and linked lists. In Go, slices are most commonly used because they expand dynamically and are convenient for working with sequences.

Example of using a slice in Go:

package main
import "fmt"

func main() {
    var numbers []int
    numbers = append(numbers, 1)
    numbers = append(numbers, 2, 3)
    fmt.Println(numbers) // [1 2 3]
}

Thus, dynamic structures are used when it is necessary to efficiently manage changing data sets without a fixed size.