Ken McGowan

“A property value can be any JavaScript value except for undefined.”
― Douglas Crockford, JavaScript: The Good Parts: The Good Parts

“The other form (called for in) enumerates the property names (or keys) of an object. On each iteration, another property name string from the object is assigned to the variable.”
― Douglas Crockford, JavaScript: The Good Parts: The Good Parts

“JavaScript, being a loosely typed language, never casts. The lineage of an object is irrelevant. What matters about an object is what it can do, not what it is descended from.”
― Douglas Crockford, JavaScript: The Good Parts: The Good Parts

“The try statement executes a block and catches any exceptions that were thrown by the block. The catch clause defines a new variable that will receive the exception object. The throw statement raises an exception. If the throw statement is in a try block, then control goes to the catch clause. Otherwise, the function invocation is abandoned, and control goes to the catch clause of the try in the calling function. The expression is usually an object literal containing a name property and a message property. The catcher of the exception can use that information to determine what to do.”
― Douglas Crockford, JavaScript: The Good Parts: The Good Parts