What kind of dog do you think this is? It jumped my back fence.?

A long time ago, before people domesticated them, dogs were all the same. Same size, color, and abilities. And then, some of them started to come into contact with humans, and their size, color, and abilities changed. Some got good at hunting, some got good at swimming. Some suddenly were born small, with curly white fur, or they just happened to be extremely large and muscly. But not all became like that. Some just stayed how they were, brown, medium, wild. Or they cross bred with other dog breeds to create some sort of hybrid. Many dogs have a little "first dog" in them. Have you ever seen those dogs at the shelter that are considered an "undetermined" breed? Or maybe they took a wild guess, but nothing seems to match the dog's breed exactly? That is because it doesn't have a breed, because it was never really domesticated to be a breed. This dog is almost pure "first dog". It isn't a certain breed, and is probably a stray. Take him to the vet to check for a microchip just in case.

Get it some food and water and call animal control. If you don't have any dogs And the dog is being friendly towards you, bring it in

The stray or feral kind. Does breed matter? Call animal control and have the poor thing picked up - if it has an owner, that is where they will look, if it doesn't it will be evaluated for health and temperament and put up for adoption.

That looks like a Rhodesian Ridgeback. They will have a ridge of hair from the neck to its tail that grows the other way

Just a poor cross bred dog. Looks scared and hungry. Put out some food and call the animal control people.

Either hungy or thristy since it looks like it had a collar on and may have escaped from its owner maybe a curr mix pit or a coon hound mix hard to say may be a mix of a mix

Heinz 57 variety, meaning a mutt of unknown origin.

Creepy tawny mix.

Scared mix. No idea.