Not actually being a back end developer, I lack some helpful concepts for the relatively small amount of programming that front end developers do (JavaScript primarily). And one concept that has always eluded me a bit is "Object Oriented Programming". What, my friends, is an object?! I had never really heard it defined. I just ran into the following and wanted to share it:

You may be wondering what OOP means by now. Object Oriented Programming is a relatively new concept, whereas the sum of the parts of a program make up the whole. Think of it this way: you are building a model car. You build the engine first. It can stand alone. It is an engine and everyone can see it's an engine. Next you build the body. It can also stand alone. Finally, you build the interior including the seats, steering wheel, and whatnot. Each, by itself is a object. But it is not a fully functioning car until all the pieces are put together. The sum of the objects (parts) make up the whole.

Continuing with the model car example, when you built the engine, you didn't use any of the parts that would later build the seats (a 350 four-barrel engine with a seat belt sticking out if the piston would look pretty silly). The point is that all the parts that made up the engine were of a certain class of parts. They all went together. Ditto with the body and then the interior.

Source: http://www.htmlgoodies.com/beyond/javascript/article.php/3470971/Java-vs-JavaScript.htm