Depending on the definition, there could be up to 18 different STL containers.
You chose the right container based on the features of the container (e.g. is it static or dynamic? Is it ordered? How long does it take to find an element in it? How long does it take to insert an element in it? How long does it take to iterate through it; etc) to match the task at hand.
I think the documentation page linked above explains these features well. Now consider what your requirements are and chose accordingly.
If you're looking for a container for a specific task, let us know what task it is (detailed requirements) and we can help to choose. For academic purposes, refer to the linked manual.
Here is a good flow chart to help decide which one to use.