“свободное и строгое равенство” Ответ

свободное и строгое равенство

== "loose" equality, compares values. It uses implicit type conversion 
to Convert one of the 2 types to the other type, or converts both types.
	> i.e. 5 == '5' is True because '5' would be converted to a int, 
    like Number('5') for example
    
=== "strict" equality, compares type and values. This is used more often
than loose equality.

Note:
x == null checks if x is null AND undefined at the same time. using == does NOT check if x was both