What is the difference between if and whether?
17037
When are "if" and "whether" equivalent?
99447
What is the difference between String? and String! (two ways of creating an optional variable)?
32293
What's the difference between if(!$variable) and if(isset($variable))?
24331
What is the difference between 'should' and 'if'?
130399
What is the difference between  and !=
17299
Conditional sentences not starting with "if"
141279
Is there a difference between  and ?
36929
Why does comparing strings using either '==' or 'is' sometimes produce a different result?
139105
Difference between if () { } and if () : endif;
16124
Use of "If there is/are"
63854
How do boolean operators work in 'if' conditions?
10298
Difference between == and === in JavaScript
78396
Logical Operators, || or OR?
120776
What is the difference between "maybe" and "may be"?
110074
What is the difference between == and equals() in Java?
124650
Is `if (condition = value)` the correct syntax for comparison?
17078
if(false==condition). Why?