Conversions from traditional to Roth IRAs are sometimes called rollovers.  But you may rollover—tax-free—from one Roth IRA to another Roth IRA.  This might be done to set up separate Roth IRAs for different beneficiaries.

You can’t convert retirement assets from a company or Keogh plan to a Roth IRA. But it’s legal to rollover from such plans to a traditional IRA, and then convert. And you can convert SEP and SIMPLE IRAs to Roth IRAs.