Check out example codes for "append array in ruby". It will help you in understanding the concepts better.

Code Example 1

a = [ "a", "b", "c" ]
a.push("d", "e", "f")
#=> ["a", "b", "c", "d", "e", "f"]

a = [1, 2, 3]
a += [4, 5]
#=> [1, 2, 3, 4, 5]

a << 6
#=> [1, 2, 3, 4, 5, 6]

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