Single and Double Quotes

PHP lets you write a string with single quotes ('...') or double quotes ("..."). They look similar, but they behave differently.

Single quotes: exactly what you type

Single quotes keep the text as it is. No variables are replaced, and almost no escape codes work.

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<?php
$name = "Maya";

echo 'Hello, $name\n';

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Hello, $name\n

Double quotes: variables and escape codes work

Double quotes put the value of a variable into the text and understand codes like \n (new line) and \t (tab).

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<?php
$name = "Maya";

echo "Hello, $name\n";
echo "Name:\tMaya";

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Hello, Maya
Name:	Maya

Escape codes in double quotes

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<?php
echo "She said \"hello\"\n";
echo "Cost: \$5\n";
echo "Folder: C:\\xampp";

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She said "hello"
Cost: $5
Folder: C:\xampp

Escaping in single quotes

In single quotes you only need to escape two things: the single quote \' and the backslash \\.

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<?php
echo 'It\'s a path: C:\\xampp';

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It's a path: C:\xampp

Which one should you use?

• Use single quotes for plain text without variables. It is clear to the reader that nothing special happens.
• Use double quotes when you need a variable inside the text or an escape code.

Either choice is fine. Pick one style for a project and keep it. The speed difference is not worth thinking about.

Quotes inside HTML

HTML attributes use double quotes, so single-quoted PHP strings keep the code readable.

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<?php
$url = "/about";
echo '<a href="' . $url . '">About</a>';

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<a href="/about">About</a>