There are a few different types of stands available on the market today when it comes to instruments.
The first type of stand is guitar stands, of which there are three main types.
Firstly, there are A frame stands. These are the most common types. A frames, as per their name, look like the letter A, and you can tell what model they are made for by the arms at the bottom. If the hooked arms at the bottom are longer, they fit acoustic and classical guitars. If they're smaller, they're made to fit electric guitars and basses.
Next, there are Guitar wall hooks. These are made to allow you to mount your guitar to a wall, for easy access and for decoration. It's highly recommended that a professional installs these.
Lastly, there are guitar rack stands. These stands are designed to fit multiple guitars in one, 3, 5 or 7 guitars are the most common amounts you can fit. Note, on these stands acoustic guitars take up a bit of extra room, so you won't be able to get 7 acoustics on a 7 guitar stand.
There are also music stands. These are designed to hold sheet music or music books, to assist you when playing music with information right in front of you
Microphone stands are, as the name suggests, a way to hold microphones in front of you. Particularly useful if you're a guitarist and want to sing, without holding a microphone.