A knife is a knife, and a hatchet is a hatchet.
I dont use one as the other unless under duress. No need to have to sharpen a knife because I was playing with it battening, when I have a hatchet. And I'm not cutting steak with my hatchet, although I could, because I recently sharpened the hell out of it.
Like @Chucem12, I have an Estwing Camp Axe, which is really the size of a hatchet. Forged from a solid lump of steel, so no head to fly off a wooden handle. Leather wrapped handle.
And then I have an assortment if knives:
-rescue knife, Byrd CaraCara (sheepsfoot, serrated). These love in the Center consoles of my old Jeep Grand Cherokee and another in my GMC Sierra, to cut seatbelts if necessary, God forbid.
-Victorinox Swiss Army knife, varying in flavors 2 to 4 layers, always in my pocket. 2 blades, scissors, saw, openers, screwdrivers
-usually a Spyderco clipped in my other pocket. Either Native 5 or Atlantic Salt, depending on my plans. If I'm at the beach or fishing it's the Atlantic.
-usually have a Leatherman on my belt if I'm not in the office.
-also keep a Swiss Army and Leatherman in my backpack, and another set in the truck.
-when camping we also have a chef's knife in the kitchen gear for food prep.
prep.
-I do also have a machete, but it rarely needs using.