▁playing ▁... K h 8 , ▁... R g 8 , ▁and ▁... g 5 , ▁often ▁followed ▁by ▁dou bling ▁ro oks ▁on ▁the ▁g - file ▁and ▁pushing ▁the ▁g - pa wn ▁to ▁g 4 . ▁ ▁Trad itional ▁ch ess ▁strategy ▁would ▁have ▁f rown ed ▁upon ▁Black ' s ▁setup , ▁since ▁their ▁pieces ▁have ▁little ▁room ▁in ▁which ▁to ▁man oe uv re . ▁In ▁the ▁early ▁ 1 9 7 0 s , ▁h edge h og ' ▁was ▁a ▁generic ▁term ▁for ▁any ▁setup ▁that ▁was ▁cr amp ed , ▁def ensive ▁and ▁difficult ▁to ▁attack ", ▁but ▁today ▁refers ▁specifically ▁to ▁this ▁formation . ▁The ▁H edge h og ▁first ▁became ▁extens ively ▁anal ys ed ▁in ▁the ▁ 1 9 7 0 s , ▁when ▁players ▁began ▁to ▁appreciate ▁the ▁rich ▁variety ▁of ▁strateg ic ▁ideas ▁that ▁arose ▁from ▁it . ▁While ▁Black ' s ▁position ▁is ▁cr amp ed , ▁it ▁is ▁also ▁relatively ▁free ▁of ▁weak ness es . ▁There ▁is ▁no ▁obvious ▁way ▁for ▁White ▁to ▁attack ▁Black ' s ▁pa wn ▁structure , ▁but ▁as ▁out lined ▁above , ▁Black ▁has ▁several ▁methods ▁at ▁their ▁dispos al ▁for ▁creating ▁. ▁Thus ▁the ▁H edge h og ▁has ▁retained ▁its ▁popular ity ▁as ▁a ▁system ▁of ▁development ▁in ▁modern ▁pra xis . ▁ ▁Early ▁history ▁The ▁ideas ▁behind ▁the ▁H edge h og ▁were ▁originally ▁developed ▁in ▁the ▁English ▁Open ing . ▁The ▁H edge h og ▁Def ence ,