Daytona windshield (along with windshields for almost all road-use motor vehicles made anywhere in the world since WWII) and back/rear glass/window are both "laminated" glass, i.e. two layers of glass adhered (laminated) to each other with thin plastic film in between them, cured by heating all in autoclave. "Delamination" usually refers to separation of these layers, commonly evidenced by formation of visible air bubbles or - pockets in between two glass layers, usually around the edges of given windshield/window. Vent/wing, door/drop and quarter (side) glass were originally produced as single pane/thickness glass that was "tempered" (=heat treated), also at times referred as "toughened", which has a tendency to "shatter" (to countless small pieces of glass) on harsh impact, especially if that impact is created by some sharp object. P.S. While I might come across a bit too pedantic about the subject, I've been reproducing windshields and other glass for vintage cars for 25+ years. P.P.S. Yes, it apparently is quite common for Daytona vent glass/window latch bases break off by shearing some glass with it.