Pipes are the main target in most levels of World of Goo. The structure has to reach near the pipe for it to activate. Most attached Goo, except Spike Goo and Balloon Goo, can activate the pipe. An activated pipe has a suction power which helps to stabilize the structure and even suspend smaller structures in midair, which is used in the pipe hanging technique. Even though attached Balloon Goo don't activate the pipe, a single Goo attached to a Balloon Goo will, which is useful to get an extra Goo Ball in a few levels such as Welcoming Unit.
The standard pipe is used for collecting most Goo Balls. The majority of normal Goo Balls can only be collected in the standard black pipe.
Pipes in general are usually found at the end of a level. If it's a long level, there is a good chance the pipe will be at the opposite side of that level that the player starts on.
- Main article: Red pipe
The red pipe first appears in Beauty School in Chapter 2. Only Small Beauty Goos can enter red pipes. The red and brown versions of Small Beauty Goo can enter the red pipe, however if both colors are present in a level, only red will be accepted in the pipe. There is an exception (see Genetic Sorting Machine).
- Main article: Green pipe
The green pipe in Alice and Bob and the Third Party only accepts Bright Green Goos. While almost all pipes in Chapter 4 are green, this version is more than a cosmetic change; it has an additional functionality change. Instead of accepting Square Goo, Launch Goo, etc, this type only accepts Bright Green Goo. Even the Infected Goo found in Alice and Bob and the Third Party will not be collected by the pipe.
The shadowed pipe is not a official pipe, but it appears in sunset levels. It is actually a normal pipe simply aesthetically solid black.