What is a good PEG ratio?

Could you elaborate on what constitutes a good PEG ratio? I've heard it mentioned in financial circles but am unclear on how to interpret it. Specifically, what range would you consider as indicative of a healthy or attractive investment opportunity? Does it vary depending on the industry or sector? And how does a PEG ratio factor into a comprehensive investment analysis? I'm interested in understanding its significance and how to use it effectively in my investment decisions.