The file formats you choose to store your data in will depend on the needs of your research project. Some questions to keep in mind when making format decisions should include:
If possible opt for standardized open source formats over proprietary formats. Standardized open source formats can be more robust than proprietary formats because they are not reliant on the continuing existence of a single company to be maintained. Some preferred open formats include:
For more tips on choosing appropriate file formats see Stanford University Library's Best Practices for File Formats.
How you name your files will have a big impact on your ability to identify and retrieve your files later. Your names should be consistent and descriptive so it's clear what each file contains. Some basic guidelines to follow are:
See this article Folder and File Naming Convention – 10 Rules for Best Practice for more tips on creating file names.