Check if a string ends with the value of the string passed as parameter..

'JavaScript'.endsWith('Script') //true
'JavaScript'.endsWith('script') //false

You can pass a second parameter with an integer value and (if present) endsWith() will consider the original string as if it was long that many characters:

'JavaScript'.endsWith('Script', 5) //false
'JavaScript'.endsWith('aS', 5) //true

It was introduced in ECMAScript 2015.