Nimbostratus cloud
Under Luke Howard's first systematized study of clouds, carried out in France in 1802, three general cloud "forms" were established based on appearance and characteristics of formation: "cirriform," "cumiliform" and "stratiform." These were further divided into upper and lower types depending on altitude. In addition to these three main types, Howard added two names to designate multiple cloud types joined together: "cumulostratus," a blending of cumulus clouds and stratus layers, and "nimbus," a complex blending of cirriform, cumuliform, and stratiform clouds with sufficient vertical development to produce significant precipitation.
Cumulus cloud
Cumulus clouds come in four distinct species, "cumulis humilis", "mediocris", "congestus", and "fractus". These species may be arranged into the variety, "cumulus radiatus"; and may be accompanied by up to seven supplementary features, "cumulus pileus", "velum", "virga", "praecipitatio", "arcus", "pannus", and "tuba".