in PHP - what is the difference in use of ' ' and " " -

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possible duplicate:
difference between single quote , double quote string in php

hi all

i new php , wanted know difference in use of ' ' , " " ?

thanks

double quotes evaluate content of string, single quotes don't.

$var = 123; echo 'this value of var: $var'; // output: value of var: $var echo "this value of var: $var"; // output: value of var: 123

it perfomance issue too, 'cause evaluation time affects interpreter, nowadays current (minimum) hardware it's not issue anymore.


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