Fix spelling

Author: brendanzab

experiments/idris/src/Fathom/Open/Record.idr

@@ -1,7 +1,7 @@
 ||| Open format universe
 |||
 ||| This module defines an open universe of binary format descriptions using
-||| records to define an inderface. By defining formats in this way, the
+||| records to define an interface. By defining formats in this way, the
 ||| universe of formats is open to extension.
 |||
 ||| I’m not sure, but this reminds me a little of the ‘coinductive universes’