If you are the only person committing files to a repository and you are working on a single computer, then you will never need to use the SVN Update menu item. This function is designed to compare your local files with the repository and check if new files or new revisions are available in the repository that are not present locally. It will then apply all the necessary changes to the local versions of these files. Remember to use the SVN Update option in TortoiseSVN regularly if you are working in a team environment or are developing a project across multiple computers.