F1 laser differences and when to uses. 

I apologize if this has already been asked, but I can’t find it when I do a search on this forum.  When searching online I get lots of contradicting results, so I wanted to ask actual users of the F1

 On the F1 there’s obviously a blue light, laser and a IR laser. When should I use the IR as compared to the Blue Light? Are they certain materials that are for the IR only and vice versa. Thanks….