A hitbox is the different areas of the body where you can hit an enemy . For example , for every area of the body , there is an invisble box -
Head
Chest
Lower Abdomen
Right Thigh
Right Calf
Left Thigh
Left Calf
Upper Right Arm
Lower Right Arm
Upper Left Arm
Upper Right Arm
Each of these areas obtain different levels of damage .
Head = - 100 HP
Chest = - 35 HP
Etc etc .
Anyway , in the recent patch , ( 14th jan ) ,
Nexon stuffed up the Hit boxes , making it extremely diffucult to hit anyone . Killing someone in game from behind is near on impossible . Also , You may fire 4 L96A1 bullets at someone straight on , and they may not register the shot at all .
<phew>
Hope I helped ,
Jordan