- Study
- A study (project) groups together data submitted to the archive and controls its release date. A study accession is typically used when citing data submitted to ENA. Note that all associated data and other objects are made public when the study is released.
- Sample
- A sample contains information about the sequenced source material. Samples are associated with checklists, which define the fields used to annotate the samples. Samples are always associated with a taxon.
- Experiment
- An experiment contains information about a sequencing experiment including library and instrument details.
- Run
- A run is part of an experiment and refers to data files containing sequence reads.