The four types of chromosomal mutations?

There are four basic types of point mutations that can occur:

Substitution: This kind of mutation switches with another base to create an irregular sequence.
ex:) NORMAL - ABCDEFG
SUBSTITUTION - BACDEFG

Insertion: This kind of mutation involves the insertion of an extra base to the sequence.
ex:) NORMAL - ABCDEFG
INSERTION - ABHCDEFG

Deletion: This kind of mutation deletes or loses one of the bases in the sequence.
ex:) NORMAL - ABCDEFG
DELETION - ACDEFG

Frameshifts: This kind of mutation is where a sequence has an insertion or deletion, altering it. Since the sequence is divided into three bases to each section, which are called codons, the insertion or deletion of one of the bases can alter the codons completely, creating a different sequence, known as a frameshift.
ex:) NORMAL - ABC DEF GHI
FRAMESHIFT - BCD EFG HI

Those are the four basic types of point mutations, however there are other known mutations.
translocation,substitution,insertion,deletion