Ibanez' naming methodology is incomprehensible gibberish, all you need to know is that 'Art' prefix guitars are trying to appeal to a distinctly different and more traditional market segment than all it's 'Rock' range.
The original Artist series guitars from the late 70's were a kind of 'signature' instrument for Ibanez signifying their move away from outright plagiarism of the established brands, a bit like the Yamaha SG series, it was an attempt to produce an 'original' looking instrument with a respectable reputation amongst professional musicians.
The earlier 'Art' series guitars are therefore considered to be professional quality instruments although this became diluted through the 00's as lower quality models were introduced.
These are broad brush strokes, I'm no historian, but you'll get the idea I'm sure.
