The world itself is not our foe because God created everything in it to be enjoyed by us within certain boundaries but when we fall so much in love with the things it to the extent of putting God behind,we become worldly walking in worldliness or walking in "Man-centered" way of life.Jesus proclaimed the first greatest commandment that "You shall love the LORD your God with all your heart,with all your soul and with all your mind" Matthew22:37. The "With all" means there is neither partial serving of God nor serving Him with other gods.
A worldly Christian is the one who partakes in earthly things as in pre-salvation is not yet truely saved.Worldliness is common over the Net,there is sarcasm,mirth,porn,obscenity,scam,idolatry etc.The norm is prevalent and that's what many people do and talk about 'cause it's what they know.
However the Word says "The love of world is enemity with God." (James4:4),you cannot serve two masters,you either love one and hate the other.
I beseech you brethren to walk in Spirit.