Sadly terminology is lax in the cannabis world, and people often use words erroneously. Resin and Rosin are one letter apart, and while often used interchangeably, are quite different creatures when it comes down to using. While both are cannabis extracts, the similarity stops there.
Live Resin (Resin)
One way to remember the difference is that the second letter of ‘Resin’ and the second letter of ‘Terpene’ are both ‘e’.
Live Resin begins with fresh cannabis, not dried and cured. The cannabis is quickly frozen which prevents the cannabinoids from breaking down and maintains the terpenes levels from the point of harvest. After freezing, the frozen material is processed (propane, butane, or agitation) without heat to separate the trichomes from the buds and sugar leaves and preserve a full-spectrum terpenes profile as close as possible to the growing plant.
One way to remember the difference again is that the second letter of ‘Rosin’ and the second letter of ‘Hot’ are both ‘o’.
Rosin starts with dry and cured cannabis. Extreme pressure and heat are used to extract the oils from the trichomes. An old fashioned method for doing this involves a hair dryer. The heat required undoubtedly destroys some terpenes, but a saving grace is that there are no solvents to purge.