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Fortran's identity is array math. Operations apply element-wise without explicit loops — the compiler vectorizes for you, often beating hand-written C.

program demo
    implicit none
    integer, dimension(5) :: a, b, c
    integer :: i

    a = [1, 2, 3, 4, 5]              ! array literal
    b = [(i*10, i = 1, 5)]           ! 10, 20, 30, 40, 50
    c = a + b                        ! element-wise

    print *, c                       ! 11 22 33 44 55
    print *, sum(c)                  ! 165
    print *, maxval(c)               ! 55
end program demo

Fortran arrays are 1-indexed by default. You can declare any range:

integer, dimension(0:9) :: zero_indexed     ! 0 to 9
integer, dimension(-5:5) :: shifted         ! -5 to 5

Built-in array intrinsics are extensive: sum, product, maxval, minval, count, any, all, dot_product, matmul, reshape, pack, unpack.