A versioned view is formally defined as:

• A set of component versions and reference set member versions defined by characteristics of their effectiveTimes.

From a practical perspective, a versioned view is the result of filtering the full release files based on criteria that return a consistent representation of the content of these files as it was (or would have been) at a particular point in time.

The three main versioned views are:

• The full view, which is a view of SNOMED CT that includes all versions of all components and reference set members in a full release.

• A snapshot view which is a view of SNOMED CT that includes the most recent version of all components and reference set members at a specified point in time.

There are two distinct types of snapshot view:

• A current snapshot view, which is a snapshot view for the date of the most recent release.

• A retrospective snapshot view, which is a snapshot view for a specified snapshot date.

• A delta view, which is a view of SNOMED CT that contains only rows that represent changes to components and reference set members since a specified date or between two specified dates in the past. 

There are two distinct types of delta view:

• The current delta view, which is a delta view for the date range between the most recent release date and the immediately preceding release date.

• A retrospective delta view, which is a delta view for a specified date range.