User blog comment:Seieireppa/A little information about my next project after GE∑:TMoP/@comment-14812118-20150417000340/@comment-1419424-20150417020241

Delta (properly the uppercase version, although I couldn't find that one on my keyboard; also, lower-case delta is cooler) represents change and is used in mathematics to denote a change between one state and the next. I felt it was appropriate for use here.