Custody vs Guardianship: Kaunsa hai kya?

Bhaisahab, please help. Mere samajh mein kuchh problem hai. In dono terms ki definition, kaam aur characteristics kafi similar hai, lekin main ye samajh nahi paya ki dono kaunse circumstances main use kiya jaata hai. Custody kahaan se aa gaya hai, Guardianship kahaan se. Kya custody isse lagbhag adoption ka case hai, aur Guardianship special cases ke liye, jaise baby ki mother ki death hogi to? Ya unmein dono se alag-alag scenario hai? Main samajh nahi raha ki kahaan se kahaan tak dono concepts use kaise kiye jaate hai. Please koi example ya case law share kar do jisse meri samajh ho jaye. - confused student.