First of all, welcome to TB! As you might imagine, this question has been asked before. By last count, it had been asked and discussed, 3,786 times.
At the top of this forum, you'll find this:
BASS FORUM LINKS (Newbie Links): PLEASE READ BEFORE POSTING NEW TOPICS
At that link, you'll find the "Beginner's Guide to Buying..." wiki in addition to specific links that answer your question in detail.
Then, there's the good old search function that can bring you to an enormous amount of information that will answer your question with details you likely didn't even realize were relevant.
Doing your homework here will actually lead you more quickly to a comprehensive answer than posting a common question and waiting for folks to chime in-- if they even do.
For many, many reasons, you should be looking for a "3/4." Bass sizes are not standard, so that categorization encompasses basses of different physical sizes and vibrating string lengths.
Pull up a chair and dig in.
Oh, and please fill out your profile. It helps us to help you and to get to know you better.