The title of this section is perhaps a little misleading. The title appears to imply that we're going to look at equations which involve any radicals. However, we are going to limit ourselves to equations including square roots. The techniques we are going to apply here can be utilized to solve equations with other radicals, though usually the work is significantly messier than while dealing with square roots. Thus, we will work only with square roots in this section.
Before proceeding it must be indicated as well that in some Algebra textbooks you will discover this section in with the equations reducible to quadratic form material. The cause is that in fact we will end up solving a quadratic equation in most of the cases. However, the approach is considerably different and thus we're going to separate the two topics into distinct sections in this course.
Usually it is best to see how these work with an example.