Percent-encoding

Percent-encoding, also known as URL encoding, is a method to encode arbitrary data in a uniform resource identifier (URI) using only the US-ASCII characters legal within a URI. Percent-encoding is used to ensure special characters do not interfere with the URI's structure and interpretation. Special characters are replaced with a percent sign (%) followed by two hexadecimal digits representing the character's byte value. For example, a space is commonly encoded as %20: original: http://example.com/my file.txt encoded: http://example.com/my%20file.txt Although it is known as URL encoding, it is also used more generally within the main Uniform Resource Identifier (URI) set, which includes both Uniform Resource Locator (URL) and Uniform Resource Name (URN). Consequently, it is also used in the preparation of data of the application/x-www-form-urlencoded media type, as is often used in the submission of HTML form data in HTTP requests. Percent-encoding is not case-sensitive.