Right-click the file and select "Properties" (Windows) or "Get Info" (Mac) to see when it was created, its size, and the application that created it.
If this file is causing an issue or if you are trying to identify it, consider the following steps:
If you can tell me (e.g., in a specific app, an email, or a file folder) or what happens when you try to open it , I can help you identify its purpose.