In Ruby, why Time.parse() isn't defined but Time.now() is?

Question

I think to use Time.parse(), it needs to have a

require 'time'

but why Time.now is usable but Time.parse is not?

Answer 1

My understanding is that the 'time' library extends the Time class (see time.rb). Thus, 'parse' is defined and implemented in the library, where as 'now' is a class function).