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Explain a method

A method is simply a sequence of instruction that the computer will execute from start to finish.

Eg:

 a = 10

 def shout( a )
    puts "hello!"
    a = 15
    puts a
end

 shout(a)

 puts a

 # hello!
# 15
# return nil
# 10

- The method will take one or more input and output something after the sequence of instruction.
- here, a is passed into the method shout , then assigned to a new variable 'a' and printed out as 15.
- the original local var outside is still 10.


- the method here has 3 lines of instruction. First one is output hello, second is assignment to number 15 to variable a , third one is output variable a.

- The last line in the method's instruction will be returned . If we print what the value of the method's returned , it is nil

 puts shout(a)

 # nil




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