Clash of Clans is a video game in which you form a village in which there are two main buildings that are the Town Hall and a Castle, where the troops that defend the village are located.
In this castle there is also a treasury made up of lots of Gold extracted from the mines and robberies of other villages, and from the stellar bonuses for earning 5 stars a day; an elixir for alchemy, and another black elixir for other types of magic.
Keep in mind that if you reach the maximum that allows you to accumulate the treasury of your village, you could lose the daily bonuses because there is no space to receive them. Also, although the game prevents you from being robbed of all the content, you will lose around 3% every time you are robbed.
For more information, check out this video about the Treasury at Clash of Clans: