Fundamental Rights vs Directive Principles of State Policy

Maine fundamental rights aur directive principles of state policy dono ko pehle se hi confuse kiya tha, lekin ab maine suna ki yeh do concepts bahut alag hain. Fundamental rights, jaise kanoon 14 se 18 ki madad se, vyaktigat swatantra ko bachate hain aur inki suraksha karte hain. Lekin yeh do concept dono Constitution ki Article 37 mein likhe hue 'Directive Principles of State Policy' ki madad se bhi karte hain. Pehle main samajh hi nahi pa raha ki 'Directive Principles of State Policy' yeh fundamental rights niye kya chahte hain, lekin kya woh apne aap me self-executory hone wale hain. Koi bataein?