A fusion splicer is a device used to join two optical fibers together by melting their ends. This process creates a continuous light path, which is essential for efficient data transmission in telecommunications. Fusion splicing is preferred for its low loss and high strength compared to other methods like mechanical splicing. The splicing process involves aligning the fibers precisely and using an electric arc to fuse them. This technology is crucial in the installation and maintenance of fiber optic networks, which are vital for high-speed internet and communication systems. Proper use of a fusion splicer ensures optimal performance in fiber optic applications.