They are similar in that they both alter the base sequence of DNA. This is what is meant by the term "mutations". They are different in that a point mutation (substitution), if it occurs in a coding...
Not all point mutations result in a frameshift. However, if the point mutation is an insertion or deletion, then it does result in a frameshift. This occurs because amino acids are coded in...
If a necleotude is added or deleted, the bases are still read in groups of three,but now those groupings are shifted for every codon that follows. Changes like those are known as frameshift mutations.