Please add a simple explanation on rationale behind “Channels" concept somewhere in "Learning" section of GDL Center.
Very few GDL users have even basic understanding of channel I/O architecture concepts.
Various GDL built-ins call channels extensively, but the concept of channels just appears in GDL Reference Guide out of nowhere (being listed in commands/keywords definitions), and is completely omitted from structured “Learning" section.
Basic understanding of a concept/need of opening/closing I/O channel is completely lost on any new user.
It may need to be included in structured learning section, and possibly added to other sections of GDL Center pertaining to speed of operations, for instance.