An abstract is a short description of an article
Articles in the sciences and social sciences often include an abstract at the beginning of each article.
History articles generally don't include an abstract in the article itself.
To find an abstract for an article, you can look up the article in one of these databases:
The subject terms assigned to a book in any college or university library catalog are standardized according to the official Library of Congress Subject Headings.
Because these terms indicate what the book or item is about. they are useful for giving you a general sense of the book's particular focus(es). This book information is from GIL Classic:
A book review (usually 1-2 pages, longer if it is a review essay) is a great way to figure out whether a book is relevant to your topic. A book review is generally not cited as a secondary source. Check with your professor about citing a longer review essay.
Book reviews can also be primary sources. For example, if you were writing a paper on pre-Civil War responses to Uncle Tom's Cabin (originally published in 1852), a review published in 1853, or 1856, or 1859, would be a primary source.
Book reviews can be found in article databases.
H-Net Reviews is also an excellent source for scholarly reviews of history books.
NOTE: Scholarly book reviews usually are published at least a year, if not longer, after a book's publication.