What is single mode fibre

"Single-mode fiber is a type of optical fiber designed to carry light directly down the fiber in a single mode. Here are some key points about single-mode fiber:
Core Diameter: It has a small core diameter, typically around 9 micrometers, which allows only one mode of light to propagate.
Reduced Attenuation: The small core size reduces the amount of light reflection, minimizing signal loss and allowing the signal to travel longer distances.
High Bandwidth: Single-mode fibers can support higher bandwidths compared to multi-mode fibers, making them ideal for long-distance communication.
Applications: They are commonly used in telecommunications and data networks where long-distance and high-speed data transmission are required."