My windshield is cracked.Is there a difference in getting a genuine Honda windshield or any other used/new one

Yes and no. No car manufacturer makes their own glass. They contract with glass manufacturers to make glass to OE (original equipment) specifications with GM, Ford, Honda or whatever car name on the glass. There are some brands of glass that are not approved by ANY car manufacturer in the world for original equipment. You definitely want to avoid those brands mainly because they reverse engineer their windshields and use substandard molds, unlike the OE glass factory. Two of the largest original equipment manufacturers in the world are PPG and Pilkington (formerly known as LOF). These two companies make many of the original glasses for auto manufacturers worldwide. Any windshield sold in the USA must meet minimum requirements for safety, not for fit. All windshields are made out of what is called AS1 laminated safety glass. It is basically 2 pieces of regular glass with .030 thick PVB plastic/vinyl sandwiched in between it. The windshield manufacturers all start with the same flat laminated glass and then they cut it to shape and bake it in a mold inside an autoclave. This is where the difference in windshields is. The OE manufacturers use OE specific molds to shape their glass and they replace them after several thousands of cycles because they may be warped or mis-shaped. Aftermarket(non OE)manufacturers sometimes buy discarded molds that are out of OE specs and use them to make windshields. You can be assured of getting a good windshield if you use a major brand like PPG or Pilkington. Just ask a few questions before you buy.