well...it depends on what part of the country or world you are living in....if you are outside the united states, i have no idea. i assume yo are within the u.s. so most likely, the snake you are inquiring about is a type of rat snake. they actually vary somewhat in color, so without a pic, noone can be sure.
diamondback rattlesnakes also have diamonds on their back. they are usually a browner color but i can only assume anyone would recognize the rattles on any rattlesnake.
you may look up a pictorial directory for snakes in your area by preforming a search on Google or Yahoo.
Black Snake Diamond Röle was created in 1981.
if it has a rattle then its a diamond back rattle snake. i don't know where you are but those are found in Arizona and other states near by. diamond back rattle snakes are extremely venomous and you should stay away from them.
if it has a diamond shape head it is poisonous
what does a white snake with black diamonds on the back mean
That is the endangered Georgia Tube snake.
it lives in North America that's where the diamond black rattle snake lives.
Lots of snakes are brown and black. You'd need to be more specific about the patterning, size, head shape, and location you spotted the snake to get a good answer.
Are you saying that the snake has like a "hood" around the head? If so, that is a cobra.
king cobra
black snake
A black snake with yellow markings typically has a dark black body with distinct yellow patterns or stripes. These markings can vary in shape and size, but they are usually vibrant and easily noticeable against the snake's dark coloration.
It depends on the snake. They can be blue, to brown, to black, to red. They can be solid or have very complex patterns. You should post a more specific question if you're asking about a certain type of snake.