Moving charges and magnetism: Ampere's Circuital law

What does Ampere's law explain?
What is Ampere's law class 12 physics?
एम्पीयर का नियम कक्षा 12 भौतिकी क्या है?
What is ampere's law and its derivation?
What is ampere's law and Faraday's law?
एम्पीयर का नियम क्यों महत्वपूर्ण है?
एम्पीयर के नियम की खोज कैसे हुई?

[@knowmore7138]

Integral part nahi samjha, B refers to magnetic field as whole in the formula and dL refers to small components of magnetic field so by multiplying them both and then integrating them... 😅 I don't understand what we are getting by doing this or by formula I am not able to understand the phenomena... Need help! ;(