Differences between Firebird and InterBase

InterBase and Firebird are distant relatives now, they have split in 1999 when InterBase 6.0 was released under open source InterBase Public License.
Since then, the difference between these database management systems became rather big, but migration from InterBase to Firebird is still easier than migration to another database since the basis is the same.
Take a look at the detailed list of differences between Firebird and InterBase (we have compared the latest released versions: Firebird 3.0 and InterBase 2017).