Microsoft has changed the Xbox One Achievements system with Xbox One. There are two types of Xbox One Achievements: achievements and challenges. Most people already know what the achievements are so here’s an explanation on challenges.
They are said to be time-bound and you can only unlock them during a specific period and if you miss the period then you won’t.
Both are said to be same but one is time-based, and there are a few differences between them. You can check out the official description below.
Achievements and Challenges:
There are also other cloud powered benefits that Microsoft has given to the Xbox One achievements:
1) It means you can get new achievements without always being required to buy new content or download title updates.
2) It allows developers to learn from and respond to user activity and focus on adding stuff that you’ll find fun. For example, let’s say a certain game is known on community forums to have a fun little sub-game of kicking chickens. Wouldn’t it be amazing if the game developers noticed the community enjoying an unintended aspect of the game and creating a challenge around it, with a reward to boot?
3) It empowers developers to involve the community (that means YOU) in the achievement creation process. If they so choose, a developer could run a contest for users to submit and vote on challenge ideas, for example, with the winning idea being released to the public as a legitimate Xbox Live Achievement.
Overall, they can be said as an improvement but not a massive one. Xbox 360 owners should already be familiar with most of them.
Via Major Nelson.