A shayre folder is one that synchronizes everything in the folder with everyone it is shared with. In the default configuration, it is a two-way street. So, if your friend(s) removes a file on their end, it will disappear on your end. But, if they put it back, it will reappear in your folder. You can adjust the settings so that it never deletes anything unless you want it to. click here for more information on changing the shayre folder settings. You could also make a copy and put it somewhere else if you want to save it forever. Or, you could also set up a one-way sync folder to do that automatically for you.