In a computer network many computers are connected to each other while a distributed system consist of many computer networks working along each other. A software is use to make computers capable of sharing data, hardware and software details with each other. Read morelink
Sometimes a distributed system refers to a network (or networks) of computers that share information with each other in order to perform a specific task. This type of distributed system can be exemplified by google performing searches across thousands of computers, or places like the National Weather Service that use hundreds or thousands of computers to solve weather-related math problems.