In phenomenology, the content of a conscious act is what occurs in the consciousness during the act of perception. The object of the act is the actual thing being perceived.
For instance, if you see a horse running through a field, the horse and the field are objects of that act of perception. The content of the act may be admiration for the speed, beauty, and grace of the horse, or nostalgia for a time when you used to ride horses, or even fear that the horse is running straight towards you. Whatever you think and feel as you watch the horse is the content of your consciousness. Needless to say, if your friend is standing beside you, also looking at the same horse, the object of her consciousness is the same as yours, but the content of her consciousness will be at least slightly different.
There are other ways of perceiving apart from seeing. You could be thinking about a horse without seeing one, or you could be considering an abstract concept such as love or duty, or struggling with a mathematical problem. Whatever is "on your mind," that thing is the object of your conscious act, and what you think and feel about it is the content of this act.