What is the importance of the OSI Physical Layer?

Physical Layer is responsible for the communication of the unstructured raw data streams over a physical medium.

Explanation: Physical Layer maintains the date rate (how many bits a sender can send per second). It performs Synchronization of bits. It helps in Transmission Medium decision (direction of data transfer).

Explanation:

Physical layer of OSI model is the first layer. This layer deals with most of the network’s physical connections - wireless transmission, cabling, cabling standards and types, connectors and types, network interface cards, and more - as per network requirements. However, the physical layer does not deal with the actual physical medium (like copper, fiber).