A contemporary quartz watch. Time perception is a field of study within psychology, cognitive linguistics and neuroscience that refers to the subjective experience of time, which is measured by someone's own perception of the duration of the indefinite and unfolding of events.
Cosine, a trigonometric function. COS cells, a cell line used by biologists. Carbonyl sulfide, (COS) a chemical compound. Cobalt sulfide, (CoS) a chemical compound. Class of service (CoS), a 3 bit field within a layer two Ethernet frame header defined by IEEE 802.1p. Class of service (COS), a configuration parameter in legacy telephone systems.
'co' isn't an actual term nor a type of company. 'corp' is an abbreviation that isn't an actual term nor a type of company. 'Inc' is just short for 'incorporated' but the abbreviation is not a type of company. all of the above refer to a corporation. 'ltd' is mainly UK only. 'llc' is a limited liability company. The best type to use is the one that fits your requirements for your specific business situation.