In Lord of the Rings Online, destiny is more than a word, it's a form of currency. Destiny Points -- gained after level 10 -- are just one of the many meta-game goals players have to work towards over their long and illustrious careers fighting the forces of evil. Of course, you can also use your built up Destiny Points to empower your monster character for PvMP sessions as well, so it's more of a fighting the forces of evil, kinda, thing.
Pretty confusing, right? That's why Turbine has this handy-dandy guide covering all the essentials about Destiny Points, how they work and what you can use them towards.