The wide range of connectors available for fibre optics include:
The Swiss company Diamond SA originally developed this connector which is common in central Europe. With protective cover for the ferrule, it is not as sensitive to dust and dirt.
A connector type developed by Japanese NTT, is less common today but still used, particularly for measuring instruments and in industrial uses.
Probably the most common SFF (Small Form Factor) connector on the market today. American Lucent Technologies developed it. With it small size, it has become very popular with operators as it is only half the size of the SC or FC and is of a very stable design with good transmission properties.
Another SFF (Small Form Factor) connector developed by Japanese NTT. It has been on the market for some time and has become popular among the several transmission equipment manufacturers since it enables very tight packing density. Also known as a Mini SC.
MTRJ is a miniature duplex optical connector. There are two multimode fibres in a single ferrule. Compared to the duplex SC, it has 2x the density. The latching coupling system is the same as an RJ 45, and it is usually used in telecom and data applications.
Another connector developed by Japanese NTT, on the market for a many years. It is probably the most common connector in the world today due to its simplicity and robustness. It is a good connector with very good transmission properties.
An older connector originally designed by AT&T that has been available for many years but is still relatively popular in industry.