Not applicable (common abbreviation for "not bad")

Notebook (abbreviated form)

नोटबुक

English Usage: "I wrote my notes in a nb."

Hindi Usage: "मैंने अपनी नोट्स एक नोटबुक में लिखी।"

Not bad (to describe something as satisfactory)

कुछ बुरा नहीं

English Usage: "Her performance was nb."

Hindi Usage: "उसका प्रदर्शन कुछ बुरा नहीं था।"

Not applicable (slang usage)

लागू नहीं (स्लैंग उपयोग)

English Usage: "He said that the plan is nb."

Hindi Usage: "उसने कहा कि योजना लागू नहीं है।"