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In the course of your research you will often create multiple versions of your data files and will need a way to keep track of it all. Version control creates a trail that allows you to see what has changed from one version to the next.
Use a systematic naming strategy to clearly identify the various versions of your files. One common method is a sequential numbering system as part of your file names (e.g. v01, v02, v03, etc.) It is also good practice to incorporate a date in the filename for version control purposes.
Keep earlier versions of your files, so that you and others can see the work that has been done. Best practice dictates that you keep at least the milestone versions of your files, ones where significant changes were made.