Point mutation vs Indels
A point mutation is a mutation causing the substitution, insertion or deletion of a single nucleotide.

An indel is a change in the number of nucleotides (either through insertion or deletion hence the name). When talking about indel most people (in evolutionary biology at least) refer to the insertion or deletion of a single nucleotide but some might refer to greater changes when talking about indels.

An indel which concern the insertion or deletion of a single nucleotide is a point mutation.