Obviously my education wasn't optimal when it comes to history. World history in particular. I'm in my thirties and it seems like everyone knows way more about, well, all of it than me. I know the big stuff, but I don't even really have a timeline to tack stuff onto. I am really interested in the idea of having a history knowledge base, but where do I start? It seems that everything I read or watch or listen to starts up assuming I already know enough to catch on. What can I do? Where do I start?
Don't start with anything overly complex or specialised - essentially, find an up-to-date, readable book about a relatively broad period. My personal recommendation in my area, for example, would be the third edition of Jonathan Spence's The Search for Modern China, a well-written entry-level book going from the mid-1300s to the present day. And as bad as Wikipedia is for many things, as an ancillary for finding about about those little things you don't already know about that turn up, it will help when you're getting through those first few books. Plus, if you want to dive deep, their bibliographies can sometimes be quite extensive (whoever did the Taiping one, for example, deserves a medal because much of my reading has been prompted by reading the books in that).
Check out the recommended books in the sidebar. Its a good way to start. Flaired users here have compiled the best books for their area of expertise/interest. If you find that you are interested in a certain timeframe/timeline, go ahead and delve further than those books!