Prorealtime is a charting package. It costs money, but they have a free version with end of day data that is pretty good. I use it myself to check end of day data on stocks. (I have a watch list I scroll through).
MT is a trading platform that works with most brokers. It's free.
So basically, you would be using one of these for your charts, because they have way more features and abilities than the charts that your broker provides.
I am not really an expert on either, but you can do a lot of the same things on both of these, such as programing Expert Advisors (automated trading), programing custom indicators, backtesting (testing your system using historical data to see how it would have worked in the past), etc.