This is one of my favorite online resources: www.investopedia.com
If you are curious what the US tax codes look like, here they are: https://www.law.cornell.edu/uscode/text/26
Yes, they need to simplify it. No, they probably won't.
Wondering where your tax refund is? Here is the IRS website to track them: https://www.irs.gov/wheres-my-refund