We get questions about guitar tabs very often. There are many different symbols and, as aschleman pointed out, many different ways to read and interpret them. That's why we've made two pages on this very topic to help with understanding how to read and use guitar tablature in a real-world way.
The first page, How To Read Guitar Tabs, is a true step-by-step approach for beginners. This page is more structured for those who are brand new to guitar and tabs. Here we will walk you through how to understand what all the basic elements of tablature are and how to look at them. We will take you through the number system and basic symbols you'll see as you work though guitar lessons.
The second page, Guitar Tab Symbols Explained, goes more in-depth with specific symbols from beginner to more advanced. If you are working through learning a guitar solo and come across a symbol you've never seen before, reference this page. This will be a great page to come back to, so be sure and bookmark it.
Guitar tabs are a great way to advance your guitar learning journey. But they are up for interpretation. So in the end, be sure to listen closely to the music itself. There is where you will find all of the answers!