How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators differ?

Question

What is the difference between `==` and `===`? - How exactly does the loosely `==` comparison work? - How exactly does the strict `===` comparison work? What would be some useful examples?

Answer 1

Equality operator in php i.e == compares value of operands while identity operator i.e, === compares value as well as data type of operands.

For example,

1)

if(120 == "120")

echo "equal";

else

echo "not equal";

Here, output will be 'equal'. Because both operands have value 120 but data types are different first is integer and second is string "120" it will ignore this.

2)

if(120 === "120")

echo "identical";

else

echo "not identical";

Here, output will be 'not identical'. Because both operands have different data types even when they have same values.