Never buy a stock just because you see someone else making money off of it. Buy a stock because you know what the company is doing, how its progressing, and the potential of where it will be in the future. Due diligence my friend. Start doing some crazy research and start understanding the way a company works in its sector and you too can become a successful investor like $heff, Investor911, Investor100, and other great investors here who put hard work into their due diligence. Just like $heff says "KNOW what you own."