What are the advantages of using single quotes versus double quotes in PHP string declarations?

Single quotes are generally preferred in PHP string declarations because they are slightly faster and do not process escape sequences or variable interpolation. This can be advantageous when working with strings that do not require special processing. However, double quotes are necessary when you need to include variables within the string or use escape sequences.

// Using single quotes for a simple string declaration
$string = 'Hello, World!';

// Using double quotes to include a variable within the string
$name = 'Alice';
$greeting = "Hello, $name!";