What is 30-days challenge?

Goal is one of the most common way for people to challenge themselves and see whether did they have any improvement or not. Sometimes when we set a goal to our-self, we didn't set a particular time to push our-self to complete it. This cause the time we spend on it is way more longer than it should be. Suddenly, one person jump out and said “We should do a 30-days challenge!” It is a challenge for one person to do in every single day in that 30 days. The goal should be easy to do, by easy I mean something that can be done for each day. Such as not watching TV, go exercise for 1 hour, take a photo each day...etc. This challenge not only can push someone continuously to do something, but also might let the person have a different view about his/her life!