Generally, {HEAD ~ program modules} include routines, programs, {TAIL ~ objects}, components, and data structures, etc. that perform particular tasks or implement particular abstract data types 
include
Generally , { HEAD ~ program modules } include routines , programs , { TAIL ~ objects } , components , and data structures , etc . that perform particular tasks or implement particular abstract data types
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH