CCleaner https://www.ccleaner.com/ – a freeium program for cleaning stuff off your computer. If you are not familiar with the term freeium, here’s a good definition from Wikipedia: https://en.wikipedia.org/wiki/Freemium
Freemium, a portmanteau of the words “free” and “premium”, is a pricing strategy by which a product or service (typically a digital offering or an application such as software, media, games or web services) is provided free of charge, but money (premium) is charged for additional features, services, or virtual (online) or physical (offline) goods. –snip–
Basically, a freeium product is one where you get some options for free, but have to pay for other options. With CCleaner, you have several options: Free (which is what I use), Professional, and Professional Bundle. They offer Home and Business versions. At some point, I will upgrade to the paid version as it offers things the free version doesn’t offer – https://www.ccleaner.com/ccleaner/download. Business versions – https://www.ccleaner.com/business/ccleaner-business-edition/lp6433. If you have multiple computers, each regular license is only good for 1 computer. Certain versions allow more computers to fall under a license. For the business versions, choose the number of computers you want to install the program on.
CCleaner is one of the most downloaded programs out there according to FileHippo: https://filehippo.com/download_ccleaner/ (you can download here as well as directly from CCleaner link in the first paragraph).
You can see a review of CCleaner on CNET: https://download.cnet.com/ccleaner/ (also has download link in addition to the above download links).