road bikes are for racing and not for comfort
hybrid bikes are for leisure and not for racing
mtb bikes are for kids and not for adults
Not even close! A hybrid is now a term used for a bike that doesn't really sit in one of the classical bike categories. You get all kinds of hybrids, some which are little more than a road bike with flat handle bars & V or disc brakes (See the
Boardman Hybrid, I ride one of these on a daily basis & this really is a peer to a normal road bike in terms of feel & all but flat out must-win performance terms). You'll also find bikes which are basically a hardtail MTB with narrow (for an MTB) rims & wearing skinny tyres. There are also a raft of bikes in between (take a look at the
Ridgeback Rapide & Rapide Equip lines). City bikes, such as the
Ridgeback Metro series, are often refereed to as 'hybrids'. Then what to make of bikes like the
Trek Portland, they're not a road bike, certainly not a mountain bike nor a crosser & certainly don't fit into the touring bike class.