Need help in trying to convert number into character code

I am using irb/ruby1.9.1/windows7.

I need to convert the letter "M" into character code. I wrote the code below:

>M

I expected the result to be 77. But the result was "M".

How can I make the letter into chara开发者_开发百科cter code?

Why not use ord

"M".ord #=> 77

Try method ord

'M'.ord

in order to get the character code.