This article is self-explanatory. DERP! An Iron bar is a bar of iron. Not steel, not bronze, iron. Its like a bronze bar, but its iron instead. A metal bar that is made of iron. Do you get where I'm coming from? Idiot.
How can I obtain this...Iron bar?Edit
If you're lazy and just want a bloody Iron bar, buy one at the Grand Exchange. However, if you absolutely must be self-sufficient to the point of complete impracticality, you can mine an iron ore, then smelt it. But theres only a 50% chance it turns into a bar, the other 50% of the time it becomes self aware and pisses off. However, an update Jagex did made it so that Iron ores piss off less with a higher Smithing level! Funny that.
Unless you're a l33t H4xx0r, you'll never manage to smelt it 100% of the time...well not without some fancy pants enchanted ruby ring...I hate details...
And thats about as much as I can say on that.