Unitary systems concentrate the power within the central government and little or no authority is granted to the component areas. In contrast federal systems allow first-order civil divisions to have some autonomy while the central government maintains authority over some areas.
Take a moment to compare and contrast the strengths and weaknesses of each system.
This is a discussion post so i need about a half a page single space with in text citation and references.
Hereare good discussions of the differences between unitary and federal governments:
http://guides.skylinecollege.edu/c.php?g=279117
http://www.lewishistoricalsociety.com/wiki/tiki-print_article.php?articleId=136
http://www.primohistory.com/Standard%2012.9.3%20Federal%20Confederal%20unitary%20Systems%20of%20Government.pdf
https://devry.vitalsource.com/#/books/9781269724821/cfi/0!/4/2/2@0:0.125 Page58