Stephen Hawking – the man who made astrophysics understandable – is no more. The English physicist passed away on March 14, at the age of 76, and left behind a legacy of irreplaceable knowledge with his contributions in the fields of general relativity and quantum gravity.

Professor Hawking was an inspiration for many, especially due to his on-going battle with ALS since the age of 21. The condition, however, was never able to deter his spirit. He is survived by his wife and three children - Lucy, Robert and Tim, and his legacy continues in the form of the many books he authored.

Stephen Hawking at One World Observatory on April 12, 2016 in New York City.
Stephen Hawking at One World Observatory on April 12, 2016 in New York City.Bryan Bedder/Getty Images for Breakthrough Prize Foundation

Here are the top five must reads from the man himself.

    1. A Brief History of Time: Published in 1988, this book elaborates on cosmology. What makes the book irresistible is he way Hawking had written it – especially readers who have no prior knowledge of scientific theories. He talks about space and time – about the building blocks that make up the universe and the forces that drive it.
    2. The Grand Design: Published in 2010, the book examines the history of scientific knowledge pertaining to the universe and argues that invoking God is the not the answer to explaining its origins. It also discusses the 11 dimensions of the M theory – which unifies all consistent versions of the superstring theory.
    3. The Universe in a Nutshell: Published in 2001, the book shares principles and theories about modern physics. In this book, Hawking aims to "combine Einstein's General Theory of Relativity and Richard Feynman's idea of multiple histories into one complete unified theory that will describe everything that happens in the universe."
    4. A Briefer History of Time: Published in 2005, this books is an update of Hawking's 1988 A Brief History of Time. Co-written with American physicist Leonard Mlodinow, the two present readers with quantum mechanics, string theory, the big bang theory, and other topics.
    5. Black Holes and Briefer Universes: Published in 1993, this collection of essays and lectures by the professor talks about the makeup of black holes and how these could be nodes from which other universes grow.

Professor Hawking had also collaborated with his daughter Lucy and Christophe Galfard for the children's book George's Secret Key to the Universe, which was published in 2007.

It was followed up by four sequels, George's Cosmic Treasure Hunt in 2009, George and the Big Bang in 2011, George and the Unbreakable Code in 2014 and George and the Blue Moon in 2016.