Investopedia is a great resource, that I still frequent.
As far as finance learning resources go I'd check out Kahn Academy's finance section to get started, in addition browse the community forum on here as there can be pretty cool threads that you can learn a lot from, stay up to date with financial news and look up the subjects you don't understand while reading them. Check out these notes from Eric Zivot's finance classes at University of Washington: Investment, Capital, and Finance, Intro to Computational Finance. Finally, and this is drifting away from your finance specific request but we are developing a quant finance curriculum led by @Delaney, it is incredibly awesome and you can learn a lot on the statistical side that will really help you develop quality algorithms. Check out the sidebar for the webinar dates for those, or you can come in person if you are in the Boston area. Here is a link to his first lecture about linear regression. . Those are some of the things that have really helped and still do help me.
A few notes about the Kahn Academy Stuff...
The videos are about 10 minutes long but totally worth it. Sal, the narrator/instructor, can talk slow sometimes so you can speed the videos up to about 1.25x and still comprehend most of the stuff. He's also fairly knowledgeable if I recall correctly he used to be an analyst at a hedge fund.
Enjoy learning, this is an exciting field to be in right now, lots of opportunities!
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