What are the differences between UTF-8 and ISO-8859-1 character sets in PHP and how do they affect text display?

UTF-8 and ISO-8859-1 are character sets used to encode text in PHP. UTF-8 supports a wider range of characters including emojis and special symbols, while ISO-8859-1 is limited to the Latin alphabet. When displaying text in PHP, if the character set is not properly set, special characters may not display correctly.

// Set the character set to UTF-8 to ensure proper display of special characters
header('Content-Type: text/html; charset=utf-8');