From the land of bourbon - and the Bourbon Trail which I have traversed a good many times - here's what makes a bourbon. By law, no less, Federal definition and all that.
Must have a specific mix of grains - look it up, each manufacturer uses a different percent of corn, rye, etc.
Must be a specific proof range - varies by label not just manufacturer. FYI, companies like Buffalo Trace make many (like 17 in BT's case) different bourbons, even Makers makes Makers, 46 and private label stuff
Must be aged in NEW oak casks that are fire charred on the inside, cannot reuse barrels for bourbon. Used barrels around here go for $150 and up, people use them for decorating, especially the ends which have the manufacturer's name, logos, and production info printed on them.
Does NOT have to be made in KY to be bourbon, but it helps, something about the limestone-infused waters our distillers draw from.
So, no, Jack and Beam are not bourbons, they are whiskey. Jack drips moonshine, not bourbon, through charcoal but also uses ageing casks.
If you are ever planning to come to the Lexington or Louisville area, hit the internet and sign up for some of the tours the manufacturers give - often for a fee. The backstage tour at Buffalo Trace was awesome, real nitty gritty stuff. The Wild Turkey tour was, at best, "industrial", all computer controlled, etc. Beautiful location and all, but uninspiring.
Makers, Woodford and some of the others are in absolutely idyllic locations in the country. Town Branch is made here in Lexington along with Kentucky bourbon barrel ale - yes, they found a way to reuse the barrels in making ale! Not to mention the really small batch distillers that seem to pop up every few months or so, like Hartfield & Co. in Paris, Bourbon County, KY. As an aside, Hartfield is the first bourbon distiller in over a century in Bourbon County, KY.