R语言经典著作Risastatisticalcomputerprogram,madeavailablethroughtheInternetundertheGeneralPublicLicense(GPL).Thatis,itissuppliedwithalicensethatallowsyoutouseitfreely,distributeit,orevensellit,aslongasthereceiverhasthesamerightsandthesourcecodeisfreelyavailable.ItexistsforMicrosoft