Justsayn - no magic in charting and it can't fortell...

Justsayn - no magic in charting and it can't fortell announcements (although often trading by those in the know can be seen in price moves prior to announcements). All markets (not just stocks) follow price cycles that follow a specific structure (most of the time) and allow predictions based on the probabilities of price moving in a certain direction and how far. Long term rises and falls often follow mathematical patterns like Fibonacci (Fibonacci patterns can be found in many things in nature - look them up). Charting is just teasing these patterns out of the noise generated by day to day movements in prices. Charting can guide you where prices may bottom and top but they rarely help with a timing.
It generally takes a lot of study and several years practical experience to become proficient at charting - so its not for everyone. And, like most things in life - a little bit of knowledge can be a dangerous thing.