DIFF or diff may refer to:

• diff utility, a file comparison tool
• Data comparison, methods and implementations to compare texts or files
• Dominican International Film Festival
• Dubai International Film Festival
• Dublin International Film Festival
• Dharamshala International Film Festival
• a motor vehicle's differential (mechanical device)

• Oh Boy (disambiguation)
• Oh Boy (Don Cisco album)
• Oh Boy! Oberto
• Oh Boy Records
• Oh Boy (The Mood I'm In)
• Oh, Brother!
• Oh Brother!
• Oh Brother
• Oh, Brother! (comic strip)
• Oh, Brother! (TV series)
• Oh Brother Where Art Thou?
• Oh Brother, Where Bart Thou?
• Oh Bum-Suk
• Oh Bury Me Not On The Lone Prairie
• Oh! By Jingo
• Oh By Jingo!
• Oh! By Jingo!
• Oh by Jingo!
• Oh by Jingo
• Oh By Jingo
• Oh By The Way
• Oh, By the Way
• Oh! calcutta
• Oh Calcutta!
• Oh Calcutta