Why PHP variables start with a $ sign symbol?

Question

Has anybody ever thought about this question. Why we must write $var_name = value; and not var_name = value;? Yes I know that it is the syntax rule that PHP uses, but why is it a $ sign symbol?

Answer 1

Because PHP was based on Perl which used $, though the symbols Perl used were meaningful and plenty used to indicate the data type, ( such as @ used to indicate an array ) PHP just has $.

PHP in its early stages was a simplistic version of Perl but over time incorporated more of Perl's features, though one may argue PHP was for a long time a simplistic primitive version of Perl since before PHP 5.3 it did not include features that have been around in other languages such as closures/namespacing.

http://en.wikipedia.org/wiki/PHP

Larry Wall, the creator of Perl, was inspired to use $ from shell scripting: http://en.wikipedia.org/wiki/Sigil_%28computer_programming%29

Answer 2

This has been common in computer languages for a long time, that's all. Long before Perl, too! For instance, check out Commodore 64 BASIC

10 PRINT "WHAT IS YOUR NAME?"
20 INPUT A$
30 IF A$="BAHKTIYOR" THEN PRINT "HEY CHECK OUT THAT DOLLAR SIGN"

In BASIC the $ was after the variable name, however.

Answer 3

Prepending all variables with $ makes the code somewhat easier to parse, and fits in with the "Hello $var" variable-embedded-in-string idea.

Answer 4

Funny answer:

Think in PHP variables as persons, you name a person and assign it a job!

But that person will refuse to work if you don't pay, so, provide a dollar in first hand :)

$Jack = "drive my car" ;

Just bringing fun to the "Game"! Enjoy!

Regarding a real answer:

The $ sign was chosen in early times of computer coding, because it was a sign present in virtually all char set codes, and a sign rarely needed within programming languages!