, ▁word ▁processing ▁documents , ▁instant ▁message ▁histor ies , ▁files ▁saved ▁from ▁account ing ▁programs , ▁spread sheets , ▁internet ▁browser ▁histor ies , ▁databases , ▁the ▁contents ▁of ▁computer ▁memory , ▁computer ▁back ups , ▁computer ▁print outs , ▁Global ▁Position ing ▁System ▁tracks , ▁logs ▁from ▁a ▁hotel ’ s ▁electronic ▁door ▁lo cks , ▁and ▁digital ▁video ▁or ▁audio ▁files . ▁ ▁Many ▁courts ▁in ▁the ▁United ▁States ▁have ▁applied ▁the ▁Federal ▁R ules ▁of ▁Ev idence ▁to ▁digital ▁evidence ▁in ▁a ▁similar ▁way ▁to ▁traditional ▁documents , ▁although ▁important ▁differences ▁such ▁as ▁the ▁lack ▁of ▁established ▁standards ▁and ▁procedures ▁have ▁been ▁noted . ▁In ▁addition , ▁digital ▁evidence ▁tends ▁to ▁be ▁more ▁vol umin ous , ▁more ▁difficult ▁to ▁destroy , ▁easily ▁modified , ▁easily ▁dup licated , ▁potentially ▁more ▁express ive , ▁and ▁more ▁readily ▁available . ▁As ▁such , ▁some ▁courts ▁have ▁sometimes ▁treated ▁digital ▁evidence ▁differently ▁for ▁purposes ▁of ▁authentication , ▁he ars ay , ▁the ▁best ▁evidence ▁rule , ▁and ▁privile ge . ▁In ▁December ▁ 2 0 0 6 , ▁strict ▁new ▁rules ▁were ▁en act ed ▁within ▁the ▁Federal ▁R ules ▁of ▁Civil ▁Pro cedure ▁requiring ▁the ▁pres ervation ▁and ▁dis closure ▁of ▁electron ically ▁stored ▁evidence . ▁Digital ▁evidence ▁is ▁often ▁attacked ▁for ▁its ▁authentic ity ▁due ▁to ▁the ▁ease ▁with ▁which ▁it ▁can ▁be ▁modified , ▁although ▁courts ▁are ▁beginning ▁to ▁reject ▁this ▁argument ▁without ▁proof ▁of ▁tam per ing . ▁ ▁Ad miss ibility ▁Digital ▁evidence ▁is ▁often ▁ruled