The importance of using === instead of == in php!
1736
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators differ?
33974
How does true/false work in PHP?
62129
In PHP (>= 5.0), is passing by reference faster?
43522
What is the "?" symbol in URL used for in php?
156145
Should we always override equals?
76012
Why are functions and methods in PHP case-insensitive?
144910
Inadvertent use of = instead of ==
156604
Why does "true" == true show false in JavaScript?
38430
In PHP, what does the ${$ } syntax do?
37909
Understanding nested PHP ternary operator
126174
What is the difference between != and  operators?
39634
Are PHP functions case sensitive?
27729
Why and how do you use anonymous functions in PHP?
32232
How does the "&" operator work in a PHP function?
62074
Which is more effective: if (null == variable) or if (variable == null)?
34563
Why does PHP consider 0 to be equal to a string?
1260
PHP If/Else Argument and PDO Objects