I’m not confident in my ability to explain it more clearly. However I highly recommend reading Sipser[1] because his treatment of the subject, and many others,

I’m not confident in my ability to explain it more clearly. However I highly recommend reading Sipser[1] because his treatment of the subject, and many others, is as clear as can be. [1] https://www.goodreads.com/book/show/400716.Introduction_to_the_Theory_of_Computation https://www.goodreads.com/book/show/400716.Introduction_to_t...