# Algebra-Specific Documentation

Secondo can be extended by algebra modules. Such an algebra
provides some new data types and operators. It can use the
types of other algebras. Operators are directly available
in the executable language of Secondo and partially also in the Optimizer. In this section, we provide
some files describing specific algebra modules:
## Hadoop-Parallel-Algebra

## Distributed2-Algebra

## Raster2-, Tile-, and GIS-Algebra