A crucial part of ensuring that research data can be used, shared and reused by a wide-range of researchers, for a variety of purposes, is by taking care that those data are accessible, understandable and usable.This requires clear data description, annotation, contextual information and documentation that explains how data were created or digitised, what data mean, what their content and structure are, and any manipulations that may have taken place. Creating comprehensive data documentation is easiest when begun at the onset of a project and continued throughout the research process.
Good documentation ensures your data can be:
Data quickly becomes unusable because key details of the context have been forgotten, so ensure you keep enough information to interpret the data.
Whatever you need to make sense of your data should be kept with the data files themselves. Lab-based research is often recorded in a lab notebook, which should be kept safe. However, the practice of keeping a research journal can be used for any research. It’s a good idea to record the notebook page number with the data files, and if possible, scan the page(s) in and keep them with the data too.
This information also helps when deciding ownership and assigning credit, so make sure you keep a note of who collected the data and when, especially if it's not you.
All of this extra information is collectively known as metadata. There are a number of metadata standards in use in different disciplines, along with more generic standards, available too.