If characters such as blanks and punctuation are passed in an HTTP stream, they might be misinterpreted at the receiving end. URL encoding converts characters that are not allowed in a URL into equivalent hexadecimal escape sequences. The WebUtility.UrlEncodeToBytes(Byte[], int, int) method creates a URL-encoded byte array.

URL decoding replaces hexadecimal escape sequences with corresponding ASCII character equivalents. For example, when embedded in a block of URL-encoded text, the escape sequences %3c and %3e are decoded into the characters < and >.