The essential two components:
a README file that describes the files in a folder and details about the work on a high-level, as well as any dependencies/assumptions
a codebook that defines specific details of data the variables you use, column headers for spreadsheets, other relevant specifics
Data must be documented to be used properly by you, your colleagues, and other researchers in the future. Data documentation (also known as metadata) enables one to understand your data in detail and will enable other researchers to find, use and properly cite your data. Researchers can choose among various metadata standards, often tailored to a particular file format or discipline. One such standard is DDI (the Data Documentation Initiative), designed to document numeric data files.
Following are some general guidelines for aspects of your project and data that you should document, regardless of your discipline. At minimum, store this documentation in a readme.txt file or the equivalent, together with the data. One can also reference a published article which may contain some of this information.
| Title | Name of the dataset or research project that produced it |
| Creator | Names and addresses of the organization or people who created the data |
| Identifier | Number used to identify the data, even if it is just an internal project reference number |
| Subject | Keywords or phrases describing the subject or content of the data |
| Funders | Organizations or agencies who funded the research |
| Rights | Any known intellectual property rights held for the data |
| Access information | Where and how your data can be accessed by other researchers |
| Language | Language(s) of the intellectual content of the resource, when applicable |
| Dates | Key dates associated with the data, including: project start and end date; release date; time period covered by the data; and other dates associated with the data lifespan, e.g., maintenance cycle, update schedule |
| Location | Where the data relates to a physical location, record information about its spatial coverage |
| Methodology | How the data was generated, including equipment or software used, experimental protocol, other things one might include in a lab notebook |
| Data processing | Along the way, record any information on how the data has been altered or processed |
| Sources | Citations to material for data derived from other sources, including details of where the source data is held and how it was accessed |
| List of file names | List of all data files associated with the project, with their names and file extensions (e.g. 'NWPalaceTR.WRL', 'stone.mov') |
| File Formats | Format(s) of the data, e.g. FITS, SPSS, HTML, JPEG, and any software required to read the data |
| File structure | Organization of the data file(s) and the layout of the variables, when applicable |
| Variable list | List of variables in the data files, when applicable |
| Code lists | Explanation of codes or abbreviations used in either the file names or the variables in the data files (e.g. '999 indicates a missing value in the data') |
| Versions | Date/time stamp for each file, and use a separate ID for each version (see file organization) |
| Checksums | To test if your file has changed over time |
Your metadata can go in a variety of places: