EAN is International Article Number. These numbers are used worldwide for marking products often sold at retail point of sale. The numbers encoded in EAN-13 bar codes are product identification numbers. Aerse supports queries using EAN-13 and UPC codes.
CAS Registry Numbers are unique numerical identifiers assigned by the "Chemical Abstracts Service" to every chemical described in the open scientific literature. Access to CAS service is limited and Aerse supports only basic searches using CAS registry numbers.
It is possible to compare any products. Only feasible properties are used for compare. For example, if first product has boolean property and second doesnt have, then first product will be marked as better.
Example: Nokia N900 == Desire