When you click to save something on your device, this stores the data. You can save the data on your computer in your files, or on the cloud. You are given the option of where to store it when you click save. If you lose things during the save process, they can often be found under the Downloads folder.
If you are writing in a Word document, saving the document stores what you have written. Anything you write or create that you don’t save will not be there if you exit that program and return.
Some new computers have an auto save option for documents which can be very useful! A short-cut to save a file is to combine the control key with the letter ‘s’.