Network planning and design is like making a map or drawing a picture but with computers and networks instead of roads or houses. It includes deciding what kind of computer networks should be created (like a group of computers around a room, or computers all around the world that are connected together), and then figuring out how to make sure those computers can talk to each other and exchange information. To do this, you need to plan out the type of connectors that should be used, where the cables should go, and how the computers should be connected together. Once everything is planned out, you can then design a network to make sure all the computers can talk to each other.