The main uses of pipelines are oil and gas together with the utilities of water and sewage. They can also be used for a few other types of product such as pulverised coal in oil.
Pipelines allow for moving large quantities over long distances. Despite initial investment, pipelines are the cheapest way of moving liquids (particularly oil and gas) over long distances. Local networks can add flexibility by delivering to a wide range of locations (such as supplies of water and gas to homes).
Some limitations are that it is slower (typically moving at less than 10 km per hour), inflexible (only transporting between fixed points), and only carrying large volumes of certain types of fluid. There is also a huge initial investment of building dedicated pipelines.