Tasks are easy ways you can earn rewards. For example, you may be asked to watch a short clip, visit a web site or register on a web site.
Each task may only be available for a limited time, so make sure you complete a task as soon as it shows up in your list. If you leave it too long the task may close and you will miss out.
Pay careful attention to the prompts for each task; some tasks will require you to follow special instructions in order to claim the reward.