Which is a point mutation? frameshift insertion deletion missense

The definition of a point mutation states that a mutations is a point mutation if it affects only one or few nucleotides in the DNA product. We have that DNA is read in frames of 3 nucleotides. If the starting point of one frame is changed, then all frames are changed because the frames are grouped by 3 nucleotides. We have that frameshift mutations not point mutations because a shift in the reading frame affects how the rest of the DNA is read. This is the case for insertion and deletion of a nucleotide; it changes the number of nucleotides and shifts the reading frame by 1. A missense mutation is a point mutation though; it involves substituting a nucleotide with a wrong one. It involves an error only in one place and it does not change the reading frame so it affects only one nucleotide.