Thank You
That's Enough For Today, Good Work
You are a 疲れ (tired) 様 (honorific that kind of refers to whoever's being mentioned with this word). You say this to people after a day of hard work or after a good practice, etc. お疲れ様でした! I suppose the assumption here is that everyone worked until they were tired, so it was a good work, and then you thank them for it and mention how tired everyone is.
おつかれさま
The reading comes from 疲れ and 様, combined together into one word.
私の妻は私の背広をハンガーに掛る時に、「今日も一日お仕事お疲れ様でした」といつも言ってくれるんです。
When my wife puts my jacket on the hanger she always says, "Thank you for working hard again today."