that it's the most used programming language in the world, used as a client-side
It was originally developed by Netscape as a means to add dynamic and interactive elements to websites.
Using ASCII character support, it makes a string portable so that it can be transmitted across any network to any computer.
This takes a string as a single parameter & encodes the string that can be transmitted over the computer network which supports ASCII characters.
Encoding is the process of converting plain text into ciphertext.
The unescape is used to decode that string encoded by the escape function, corresponding to the escapes.