How to Write a Book Review?

What is a Book Review?

A book review is a form of literary criticism in which a book is analyzed based on content, style, and merit.(Wikipedia

A book review is NOT mere retelling of the story or content of the book. Your review should assess and evaluate the content and should tell the readers whether the author succeeded in conveying the message.

The book review is your opinion about the book you are reviewing. You should express your feelings, reflections and reading experience in your review. You should express your opinion about the book, supporting it with evidence from the book. 
There is no particular format or style to write a review. It depends on the creativity and interest of the person writing the review. 

Here are a few suggestions/guidelines for writing a review.

Bibliographic Information

Provide brief bibliographic information about the book. 

Give the title of the book as the title of your review.
Include title, author, place, publisher, publication date, edition, pages, special features (maps, etc.), price, ISBN.

Author at work 

Write the subject/theme of the book, fiction or non-fiction. What is the central theme and main characters of the work, in case the book is a fiction. 

The purpose and intent of writing the book. Identify the target audience - like is it a book meant specially for children? What category of a book it is?  

Technique (s) and styles adopted by the author like the style of narration. How the author has presented the story or the subject content of the book. Is it interesting? 

For subject books, valuate the accuracy, thoroughness, clarity and usefulness to the reader. 

Include information about the author-- reputation, qualifications, etc. -- anything relevant to the book and the author's authority especially if you are reviewing a non-fiction book.

Your Opinion

Write your personal experience reading the book – how do you relate to the characters in the book, what you liked most about the book, would you recommend this books to others, to whom the book is suitable etc.

What you feel about the book Style, authenticity and enthusiasm by which others are persuaded to read the book . Few quotes from the book may be included to illustrate your point of view. What about the characters? Did you like them? 

Will you recommend this to others? In your opinion, which category of users it will be more useful or interesting? If this is the best book you have ever read, say so -- and why. If it's merely another nice book, say so.

Conclusion
Your conclusion should summarize, perhaps include a final assessment.