0 0 7 ▁is ▁that ▁at ▁least ▁ 8 0 % ▁of ▁the ▁time ▁that ▁it ▁takes ▁to ▁download ▁and ▁view ▁a ▁website ▁is ▁controlled ▁by ▁the ▁front - end ▁structure . ▁This ▁lag ▁time ▁can ▁be ▁decre ased ▁through ▁aw aren ess ▁of ▁typical ▁browser ▁behavior , ▁as ▁well ▁as ▁of ▁how ▁HTTP ▁works . ▁ ▁Opt im ization ▁techniques ▁▁ ▁Web ▁performance ▁optimization ▁impro ves ▁user ▁experience ▁( U X ) ▁when ▁visit ing ▁a ▁website ▁and ▁therefore ▁is ▁highly ▁desired ▁by ▁web ▁design ers ▁and ▁web ▁developers . ▁They ▁employ ▁several ▁techniques ▁that ▁stream line ▁web ▁optimization ▁tasks ▁to ▁decrease ▁web ▁page ▁load ▁times . ▁This ▁process ▁is ▁known ▁as ▁front ▁end ▁optimization ▁( FE O ) ▁or ▁content ▁optimization . ▁F E O ▁concentr ates ▁on ▁reducing ▁file ▁sizes ▁and ▁" min im izing ▁the ▁number ▁of ▁requests ▁needed ▁for ▁a ▁given ▁page ▁to ▁load ." ▁ ▁In ▁addition ▁to ▁the ▁techniques ▁listed ▁below , ▁the ▁use ▁of ▁a ▁content ▁delivery ▁network — a ▁group ▁of ▁proxy ▁servers ▁spread ▁across ▁various ▁locations ▁around ▁the ▁glo be — is ▁an ▁efficient ▁delivery ▁system ▁that ▁cho oses ▁a ▁server ▁for ▁a ▁specific ▁user ▁based ▁on ▁network ▁proxim ity . ▁Typ ically ▁the ▁server ▁with ▁the ▁quick est ▁response ▁time ▁is ▁selected . ▁▁ ▁The ▁following ▁techniques ▁are ▁commonly ▁used ▁web ▁optimization ▁tasks ▁and ▁are ▁widely ▁used ▁by ▁web ▁developers : ▁ ▁Web ▁browsers ▁open ▁separate ▁Trans mission ▁Control ▁Pro tocol ▁( T CP ) ▁connections ▁for ▁each ▁Hyper text ▁Transfer ▁Pro