Dub is reggae stripped to its essentials. with peolple like scratch perry, and king tubby paving the way in the 60's. both these guys were music producers that had tons of recordings laying around and started splicing tracks together. The roots of sampling. dub is all about the BASS and badass drumming everything else cuts in and fades out Dub is the voice of the soul..
riddim is no slang, riddim is sacred. this word describes rhythmic patterns that are handed down from generations. virtually all the reggae you are familar with is based on classic riddims, shit even the james bond theme is based on a riddim. riddim is part of the soul it is ancient!