What is bind call Apply function in JavaScript?

The call, bind and apply methods can be used to set the this keyword independent of how a function is called. The bind method creates a copy of the function and sets the this keyword, while the call and apply methods sets the this keyword and calls the function immediately.

use of call and apply in JavaScript ?

You use call or apply when you want to pass a different this value to the function. In essence, this means that you want to execute a function as if it were a method of a particular object

The differences between call, apply, and bind

Both call and apply invoke a function. Their only difference is that call accepts arguments in a comma-separated fashion while apply requires arguments to be passed as an array or an array-like object.
Bind returns a function. Examples coming up.

between .call() and .apply() :
The function .call() and .apply() are very similar in their usage except a little difference. .call() is used when the number of the function’s arguments are known to the programmer, as they have to be mentioned as arguments in the call statement.
On the other hand, .apply() is used when the number is not known.
The function .apply() expects the argument to be an array. The basic difference between .call() and .apply() is in the way arguments are passed to the function.
Their usage can be illustrated by the given example.