Nowadays, cameras are getting smaller and smaller. Just look at the camera on the back of your smartphone right now! Tiny cameras are no longer just for detectives and undercover operations, and this is great news for the plumbing industry.
In the past, plumbers needed to use listening equipment, manual tools, and digging to find the exact source of a problem within the pipes, and it may have involved some trial and error. But now, when there is a clog or leak in your sewer line, camera line inspections are the norm for many (but not all) plumbers.