These clouds can be natural or man-made, and seen with other traditional species and varieties (click thumbnails for more information): -

	Accessory Clouds – only occurring in conjunction with the principal cloud types
	Supplementary Features – mostly occurring with cumulonimbus clouds
	Special Clouds – including mysterious noctilucent clouds
	Man-made Clouds – including aircraft contrails
	Optical Effects & Phenomena – effects caused clouds on sunlight, and other phenomena such as lightning and aurora