The top-level function, escape, encodes the string that is contained in the string argument to make it portable. A string is considered portable if it can be transmitted across any network to any computer that supports ASCII characters.

To make a string portable, characters other than the following 69 ASCII characters must be encoded:

ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyz
1234567890
@*-_+./

All other characters are converted either to their two digit (%xx) or four digit (%uxxxx) hexidecimal equivalent (refered to as the character's "hexidecimal escape sequence"). For example, a blank space will be represented by %20 and a semicolon by %3B. (Note that the hexidecimal numbers are: 0123456789ABCDEF).

Use the unescape function to decode an encoded sequence that was created using escape.

Code:
document.write(escape("Miss Piggy."))

Output:
Miss%20Piggy.

Code:
document.write(escape("!@#$%^&*()_+|"))

Output:
%21@%23%24%25%5E%26*%28%29_+%7C