• Provide a central repository for next generation sequencing data.
• Provide links to other resources referencing or using this data.
• Provide users with retrieval based on ancillary information and sequence comparison.
• Track studies and experiments (project metadata).
• Allow flexible submission and retrieval of ancillary data.
• Improve database efficiency through normalization of data structures.
• Separate submission from content.
• Establish basis for user-interactive submission and retrieval.

 
NCBI:
 SRA - SRA submission accession.
 SRP - SRA study accession.
 SRX - SRA experiments accession.
 SRR - SRA run accession.
 SRS - SRA sample accession.
 SRZ - SRA analysis accession.
 
EMBL:
 ERA - ERA submission accession
 ERP - ERA study accession
 ERX - ERA experiment accession
 ERR - ERA run accession
 ERS - ERA sample accession
 ERZ - ERA analysis accession
 
DDBJ:
 DRA - DRA submission accession
 DRP - DRA study accession
 DRX - DRA experiment accession
 DRR - DRA run accession
 DRS - DRA sample accession
 DRZ - DRA analysis accession
 

GSE: A GEO Series (GSExxx) is an original
     submitter-supplied record that summarizes
     a study.
GDS: Reassembled and curated GEO Datasets.
Both Series and DataSets are searchable using the 
GEO DataSets interface, but only DataSets form the 
basis of GEO's advanced data display and analysis 
tools including gene expression profile charts and 
DataSet clusters, see the Data organization 
document for more information. Not all submitted 
data are suitable for DataSet assembly and we are 
experiencing a backlog in DataSet creation, so not 
all Series have a corresponding DataSet record(s).

Raw sequence data have been uploaded to NCBI Seq-
uence Read Archive (SRA) database, and linked from
Sample and Series records, available in 'sra' format.

GSM: GEO sample unique and stable accession number.
GDS: Reassembled into GEO Dataset records by GEO
     staff.
GPL: GEO Platform accession.

 

 Link: GEO FAQ.
 

SAMN: Biosample accession number.