What is the difference between using single quotes and double quotes in the echo command in PHP?

Using single quotes and double quotes in the echo command in PHP affects how variables and escape sequences are interpreted. When using double quotes, variables will be evaluated and escape sequences will be processed. In contrast, when using single quotes, variables will not be evaluated and escape sequences will be treated as literal characters. To fix this issue, use double quotes when you want to include variables or escape sequences in the output, and use single quotes when you want to output a literal string without any variable interpolation or escape sequence processing. 

// Using double quotes to include variables and escape sequences
$name = "John";
echo "Hello, $name!"; // Output: Hello, John!

// Using single quotes to output a literal string
echo 'Hello, $name!'; // Output: Hello, $name!

Keywords

PHP echo command single quotes double quotes string interpolation

Related Questions