VCR Plus+, G-Code, VideoPlus+ and ShowView are different names for the same scheduling system for programming VCRs and digital video recorders. These names are all registered trademarks of Macrovision, whose corporate predecessor, Gemstar, developed these algorithms for use in integrated endecs.
This system was actively used for two decades, introduced in the late 1980s, and the last publication of а PlusCode was in 2010.