openfoam-dev: package of the development line of OpenFOAM, which includes major code changes that can break backward compatibility.
openfoam5: package created from the
OpenFOAM-5.xsource repository that incorporates latest code fixes without breaking backward compatibility.
paraviewopenfoam54: package of ParaView for OpenFOAM, installed automatically as a recommended package of
To install OpenFOAM-dev on Ubuntu 18.04, see: Download OpenFOAM-dev | Ubuntu
To install OpenFOAM 5 on Ubuntu 18.04, see: Download v5 | Ubuntu