User's Manual

128
Whenwespeakoffreesoftware,wearereferringtofreedom,not
price.OurGeneralPublicLicensesaredesignedtomakesurethat
youhavethefreedomtodistributecopiesoffreesoftware(and
chargeforthisserviceifyouwish),thatyoureceivesourcecode
orcangetitifyouwantit,thatyoucanchangethesoftwareoruse
piecesofitinnewfreeprograms;andthatyouknowyoucando
these things.
Toprotectyourrights,weneedtomakerestrictionsthatforbid
anyone to deny you these rights or to ask you to surrender the rights.
Theserestrictionstranslatetocertainresponsibilitiesforyouifyou
distributecopiesofthesoftware,orifyoumodifyit.
Forexample,ifyoudistributecopiesofsuchaprogram,whether
gratisorforafee,youmustgivetherecipientsalltherightsthatyou
have.Youmustmakesurethatthey,too,receiveorcangetthesource
code. And you must show them these terms so they know their rights.
Weprotectyourrightswithtwosteps:(1)copyrightthesoftware,and
(2)offeryouthislicensewhichgivesyoulegalpermissiontocopy,
distributeand/ormodifythesoftware.
Also,foreachauthor’sprotectionandours,wewanttomakecertain
thateveryoneunderstandsthatthereisnowarrantyforthisfree
software.Ifthesoftwareismodiedbysomeoneelseandpassedon,
wewantitsrecipientstoknowthatwhattheyhaveisnottheoriginal,
sothatanyproblemsintroducedbyotherswillnotreectonthe
originalauthors’reputations.Finally,anyfreeprogramisthreatened
constantlybysoftwarepatents.Wewishtoavoidthedangerthat
redistributorsofafreeprogramwillindividuallyobtainpatent
licenses,ineffectmakingtheprogramproprietary.Topreventthis,
wehavemadeitclearthatanypatentmustbelicensedforeveryone’s
freeuseornotlicensedatall.
Theprecisetermsandconditionsforcopying,distributionand
modicationfollow.