A Bitcoin Lottery Website
Since it is very expensive and time-consuming to mine Bitcoins, techy savvy people realized that they can use the collective processing power of individual computers worldwide to do it. The hardware to process Bitcoins is very expensive, a large area is needed to store the hardware, and a lot of cooling is needed to prevent the hardware from overheating. This includes buying very expensive cooling systems.
Now, with the very expensive hardware comes a very big electricity bill because a lot of electricity is needed to power the hardware and the cooling system.
Using individual computers around the world to mine Bitcoins is very cheap because no setup and maintenance are required, there no need to rent space for the hardware, and there is no need to pay for electricity and other utilities. And, doing lotteries where only a few persons will earn money from Bitcoin mining makes it very profitable for the people operating them, and not the participants.
Remember, there are cybercriminals who trick online users into installing Bitcoin mining malware or malicious Chrome Extensions, which silently uses their computer or mobile device processing or CPU power. This slows down the victims' computers or mobile devices and drains their laptop computer and mobile device batteries very quickly.
Remember, no one knows where most of those Bitcoin operators are located and who they are. So, why install an app, Chrome Extension or other software that you have no idea who created it and what it is doing when it is running on your computer or mobile device. It could steal your information or spy on you, you just do not know.