What happens when a network error occurs during a fetch request?
When a network error occurs: 1) The fetch Promise rejects with a TypeError, 2) Only network-level errors cause rejection (like DNS failure or no internet), 3) HTTP error responses (like 404 or 500) do not cause rejection, 4) Requires proper error handling in .catch() blocks, 5) TypeError provides information about the network failure, 6) Important distinction from HTTP error responses which resolve normally.