How to use OR condition in a JavaScript IF statement?

Simply use the logical "OR" operator, that is ||.

if (A || B)

Worth noting that || will also return true if BOTH A and B are true.

In JavaScript, if you're looking for A or B, but not both, you'll need to do something similar to:

if( (A && !B) || (B && !A) ) { ... }

if (A || B) { do something }