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Unit 2: Language Basics

Variables in PHP consist of the $ character and a label. A label can be created from alphanumeric Notes
characters and an underscore (_) character. A variable cannot begin with a number. The PHP
interpreter can then distinguish between a number and a variable more easily.
$Value

$value2
$company_name
These were valid identifiers.

$12Val
$exx$
$first-name

These were examples of invalid identifiers.
The variables are case-sensitive. This means that $Price, $price, and $PRICE are three different
identifiers.

<?php
$number = 10;
$Number = 11;

$NUMBER = 12;
echo $number, $Number, $NUMBER;
echo “\n”;

?>
In our script, we assign three numeric values to three variables and print them.
101112
This is the output of the script.

A Literal
A literal is any notation for representing a value within the PHP source code. Technically, a literal
will be assigned a value at compile time, while a variable will be assigned at runtime.
$age = 29;
$nationality = “Indian”;

Here we assign two literals to variables. Number 29 and string Indian are literals.
<?php
$name1 = “Piyush “;

$age1 = 25;
$name2 = “Seema “;
$age2 = 24;
echo “Piyush 22\n”;
echo “Rahul 22\n”;

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