Built-in Ruby methods

Question

If there is a defined built in ruby method, is it always preferable to use the built-in method?

If I have code such as:

if i == 0

What is the advantage to instead using the built-in ruby method?

if i.zero?

Answer 1

i.zero? works only if i is Numeric object.

i = nil
i == 0
# => false
i.zero?
# NoMethodError: undefined method `zero?' for nil:NilClass
#        from (irb):5
#        from C:/Ruby200-x64/bin/irb:12:in `<main>'