What are the applications for single mode fibers?

Hi,

Single mode fiber is used to send the data from transmitter to receiver or repeater. In single mode we can only send single signal at a time and hence it is single mode.

The Single mode fiber will have core and cladding arranged in such a way that the core has got one refractive index and the cladding has got another refractive index which will be constant through out the fiber.