what is $i in php code example

Example 1: what does $ sign mean in php

<?php

$name = "World";
echo "Hello, $name";

# $ i.e. "sigil" is used to distinguish a string variable from rest of the string.

Example 2: operators in php

if (condition)
   code to be executed if condition is true;
else
   code to be executed if condition is false;