▁requires ▁the ▁least ▁co operation . ▁Un like ▁automatic ▁finger print ▁reading , ▁which ▁requires ▁an ▁individual ▁to ▁press ▁a ▁finger ▁against ▁a ▁machine , ▁this ▁technique ▁is ▁subt le ▁and ▁requires ▁little ▁to ▁no ▁consent . ▁ ▁Psych ological / social ▁effects ▁ ▁Some ▁critics , ▁such ▁as ▁Michel ▁Fou ca ult , ▁believe ▁that ▁in ▁addition ▁to ▁its ▁obvious ▁function ▁of ▁ident ifying ▁and ▁capt uring ▁individuals ▁who ▁are ▁comm itting ▁und es irable ▁acts , ▁surve ill ance ▁also ▁functions ▁to ▁create ▁in ▁everyone ▁a ▁feeling ▁of ▁always ▁being ▁watched , ▁so ▁that ▁they ▁become ▁self - pol icing . ▁This ▁allows ▁the ▁State ▁to ▁control ▁the ▁popul ace ▁without ▁having ▁to ▁resort ▁to ▁physical ▁force , ▁which ▁is ▁expensive ▁and ▁otherwise ▁problem atic . ▁ ▁With ▁the ▁development ▁of ▁digital ▁technology , ▁individuals ▁have ▁become ▁increasing ly ▁per cept ible ▁to ▁one ▁another , ▁as ▁surve ill ance ▁becomes ▁virtual . ▁Online ▁surve ill ance ▁is ▁the ▁util ization ▁of ▁the ▁internet ▁to ▁observe ▁one ' s ▁activity . ▁Corpor ations , ▁citizens , ▁and ▁govern ments ▁particip ate ▁in ▁tracking ▁others ' ▁behav i ours ▁for ▁motiv ations ▁that ▁arise ▁out ▁of ▁business ▁relations , ▁to ▁curiosity , ▁to ▁leg ality . ▁In ▁her ▁book ▁Super connected , ▁Mary ▁Ch ay ko ▁differenti ates ▁between ▁two ▁types ▁of ▁surve ill ance : ▁vertical ▁and ▁horizontal . ▁Vert ical ▁surve ill ance ▁occurs ▁when ▁there ▁is ▁a ▁dominant ▁force , ▁such ▁as ▁the ▁government ▁that ▁is ▁attempting ▁to ▁control