Form 8606 for roth conversion

Could someone clarify this please:  On form 8606 instruction, it says you must file if "you convert tradition IRA to Roth." However, on the form itself, it seems to suggest you need to complete the form when you convert traditional IRA to Roth AND you made nondeductible contribution to traditional IRA.   So for people who converted traditional IRA to Roth, but did not made any non-deductible contributions, do they need to file form 8606?