Finally, Modules and Sequences can be combined into Paths. A path is a complete execution sequence, commencing at the Input Module and terminating at the Output Module. However, the presence of Filter Modules within a path might terminate execution of a path prematurely. In this case the event may not be a candidate for output (see Output Streams), or might redirect subsequent processing to one of several modules or module sequences. Multiple paths can be specified and may be deemed to be active or inactive. Each active path will be executed within the event loop, whereas inactive paths will be bypassed. A module can be present on multiple paths or may appear multiple times within a single path or sequence. However, it will only be executed once for each module-instance for each event. For the purposes of the next section, a module is said to be active if it belongs to an active path.