Bailment vs Pledge - Kya Hai Ye Dono?

Mujhe lagta hai kisi problem hai, lekin maine check karke nahi paya. CrPC 309 ke undr, kya aapko pata hai ki 'pledge' ek bhi type ke nahi hai, par yeh kya hota hai? Maine socha ki yeh pledge ka ek vishesh type hai, jaise mortgage ya lien, per maine koi reference nahi paya. Aur phir, kya 'bailment' to pledge ke samaan nahi hota? Lekin CrPC 306 ka mention hua hai, jo 'bailment' ke bare mein hai. Phir, kya CrPC 309 se juda ho, ya woh toke different hai? Aur kya aap jante hain kis case mein 'pledge' ka use karta hai?