Looking at plumbing in a house have you ever wondered what different things are? There is that usual loop of pipe, which for no apparent reason loops down from ceiling in the basement?
Or the two copper pipes about a foot apart one above the other that are sticking straight out and capped off?
The answer is, they are what is called “a pre-plumbed hook up” for adding a water softener. They are typically found close to the water heater.
If you are buying a home and the water pipes are CPVC (a cream colored hard plastic the same as the photo) don’t waste your money paying the builder to install the dropped loop, unless its been done for free.
You can see, it is not something that would be difficult to do your self or your plumber could do when you are having a softener installed.