Reality is the one word that describes everything we live in, everything we know, knew, and will. It represents time, space, and all the other possible dimensions. But what exactly is reality? In his book, The Bitter Truth of Reality, author Mahmoud Elsayed attempts to answer this complex query by taking a journey through physics, biology, human anatomy, history, philosophy, and even religions. Hopefully, by the end of this book, the reader will find an answer to this question that sits at the top of the existential questions list. It also offers an opportunity for its readers to come to terms with being an ordinary human within the shadow of the grand scheme of all existence. Humanity currently lives in a time when rationality is prioritized above everything else. We define reality by what our minds process to be true from data our senses can provide us. As a result, each of us treats any idea, belief, or experience that fails logic as impossible or flawed. But should humanity put faith in how our limited biology interprets reality around us, and can we rely on our minds to tell us everything there is to know about us, our universe - or even what's outside of it? This book describes how mankind, in search of objective insight, has entrusted science with the duty of filtering reality from the surreal. However, in place of answers, scientific inquiry might be doomed to discover only more questions. In the end, how can we tell apart what is real, and how does this change what we know about ourselves? The more we develop as a species, the more questions we will ask about the truth of our existence. Are we here on purpose? Or are we the result of some cosmic accident? More inquires and discussions in The Bitter Truth of reality.