figure dc js interactive example on its official website crossfilterthe javascript mapreduce library javascript isn' the greatest language for data crunching but that didn' stop peoplelike the folks at squarefrom developing mapreduce libraries for it if you're dealing with dataevery bit of speed gain helps you don' want to send enormous loads of data over the internet or even your internal network thoughfor these reasonssending bulk of data will tax the network to the point where it will bother other users the browser is on the receiving endand while loading in the data it will temporarily freeze for small amounts of data this is unnoticeablebut when you start looking at , linesit can become visible lag when you go over