What does the .= operator mean in PHP?

Question

I have a variable that is being defined as

$var .= \"value\";

How does the use of the dot equal function?

Answer 1

the "." operator is the string concatenation operator. and ".=" will concatenate strings.

Example:

$var = 1;
$var .= 20;

This is same as:

$var = 1 . 20;

the ".=" operator is a string operator, it first converts the values to strings; and since "." means concatenate / append, the result is the string "120".