The Crowe film was an amalgam of a few books, then tweaked a bit. Master and Commander is the first book in the series, Far Side Of The World is the 10th, which the plot is mainly derived from, but then changed from the War of 1812 between Britain and America to a few years earlier against the French in case US audiences didn't like being the enemy. It is a fine film based on a truly magnificent series of books.
While the likes of Bernard Cornwell and Simon Scarrow produce rollicking good yarns yet pay attention to historic detail as much as they can, Patrick O'Brian is in a different class all together. The quality of his writing is outstanding, far superior even to most of the writers of classic all time novels. Dickens wrote pulp fiction compared to this.
The novels are not just tales of Napoleonic era naval conflicts, which are superbly brought to life and are realistic since are often taken from real incidents of the time, but they are deep dives into espionage, politics, discovery, wildlife, medical techniques, belief's and advances, philosophical meditations on love, power, relationships, religion, class, gender and, er philosophy even. Frankly it touches on just about everything. That could be tedious, were they not so well written. O'Brian is able to fill a chapter where nothing but the monotony of naval routine takes place for weeks and no event of any real note occurs and yet you are devoured by it. The action, when it comes, is outstanding, but these are not books where it is one buccaneering exploit after another. Rather, they usually build slowly. These are masterpieces like The Godfather I and II, not episodes of Miami Vice. It is the difference between a necking spiced Rum and Coke and sipping a Diplomatico Ambassador over ice.
One of the first Aubrey-Maturin novels I read was Desolation Island. In it there is a gripping chase through heavy South Atlantic seas against a Dutch Man O War. It was so gripping and powerful I had it fixed in my memory that it took up half the book. When I got back round to re-reading it - if you like the series, you will finish it then go back - I was amazed to find the chase itself was actually only a handful of pages.
Each book is also very different, in different parts of the world, against different enemies. Some are even predominantly on land. Maturin is an incredible character, not only what he brings to each situation as a protagonist, being Irish/Catalan assisting the British Navy, Physician rather than simple naval surgeon, Natural Philosopher and member of The Royal Society and Secret Agent, but also as a vessel to see the society of that age of the world through.