What is True Altruism?

One time as I decided to research on altruism on the Net, I found myself disturbed by other people's impressions. Some comments define altruism as "the desire to please others." I found it disagreeable because I hate pleasing other people. Yeah, no kidding, it's one of the things I hate doing the most. But aside from that, I've heard people advise, stop trying to please everybody. In addition, pleasing others in not necessarily doing good. I agree with this. But why is pleasing others not necessarily good? Isn't that a show of love of others in the Christian manner, as some would say?