The video tutorial explains forward iterators, highlighting their multipass guarantee, which allows multiple accesses to the same element before moving forward. It contrasts forward iterators with input iterators, which only allow single pass validity. The tutorial also covers mutable forward iterators, which meet both input and output iterator requirements. A code example demonstrates the use of forward iterators and compares them with back insertion iterators, showing how forward iterators maintain validity while back insertion iterators do not. The video concludes with a preview of bidirectional iterators.

How does the increment operation behave differently for back insert iterators compared to forward iterators?

What happens to the values in the back insertion vector when using a back insert iterator?

In what way does the forward iterator allow for multiple writes to the same memory location?