Modification requirement on a particular file can be achieved by checking out a file from the application and then making revising that file. Checking out allows that particular user to work on that specific file. The other users can view the file but won’t be able to work on it. Checking out essentially means downloading the files on your local computer but an instance of the file will remain in the application. You can open to view a checked out file. After making the revision the file can be checked in to be made part of the application again i.e. a revised version of the same file will be uploaded in the application. Also, you cannot check out the same file multiple times.
Follow the given procedure to check out the selected file(s) from a specific folder:
Links:
Accessing & Understanding Collection Folder & File Screen