How does URL encoding work?

URL encoding, also known as percent-encoding, is a mechanism used to encode special characters in URLs to ensure that they are transmitted correctly over the internet. Here's how it works:

1. Character Encoding: URLs can only be sent over the Internet using the ASCII character set. Characters outside this set, such as spaces, punctuation, and non-ASCII characters, must be encoded.

2. Percent-Encoding: Each character that needs to be encoded is replaced by a percent sign (%) followed by two hexadecimal digits that represent the ASCII value of the character. For example:

   • Space ( ) is encoded as %20
   • Exclamation mark (!) is encoded as %21
   • Ampersand (&) is encoded as %26

3. Reserved Characters: Some characters have special meanings in URLs (like ?, &, =) and should be encoded if they are part of the data rather than the URL structure. For example, if you want to include an ampersand in a query parameter, it should be encoded as %26.

4. Decoding: When a URL is received, the browser or server decodes the percent-encoded characters back to their original form for processing.

5. Usage: URL encoding is commonly used in query strings, form submissions, and when passing data in URLs to ensure that all characters are safely transmitted.

In summary, URL encoding transforms special characters into a format that can be safely transmitted over the internet, ensuring that the data remains intact and correctly interpreted.