when we can use $ in constants?

Answer 1

Constant does not need the $, right?

Answer 2

there are two ways of defining a constant
first way is using define(varname,value)
another way is using a underscore in the beginning of variable like $_pi=3.14

Answer 3

due to what I have understood so far it is used for declaring variables in PHP, without it your variables would be useless

Answer 4

$ is used as the beginning of any variable name in php.

Answer 5

It is used to declare a variable

Answer 6

It is used to declare a variable

Answer 7

where can we use constant anyone can explain with example

Answer 8

we never use $ for constants.