As the site says: "This database stores curated gene expression DataSets, as well as original Series and Platform records in the Gene Expression Omnibus (GEO) repository. Enter search terms to locate experiments of interest. DataSet records contain additional resources including cluster tools and differential expression queries."

Essentially, you can view it as a 'PubMed' of Gene Expression data.

The data at GEO is large and extensive, and you need to make sure you are looking at the right data. Otherwise, your analysis will not produce meaningful results.

In this section we are going to look at: