Where can I read about conditionals done with “?” and “:” (colon)? [duplicate]

Answer 1

That would be the conditional operator. It's pretty much a single line if/then/else statement:

if(someCondition){
    $x = doSomething();
}
else{
    $x = doSomethingElse();
}

Becomes:

$x = someCondition ? doSomething() : doSomethingElse();