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A nice, brief book from one of the people involved in the initial creation and subsequent development of Unix and the programming environment that grew up around it. A somewhat technical book, it covers the early history of the development of Unix itself and also the development and growth of the huge set of tools and programs that grew out of what Unix was able to provide as an operating system.

Chapter one looks at the history of the author's education, as well as the history of Bell Labs before and after he joins it. It also introduces the large and varied cast of people he would work with while at the lab, many of whom will be familiar to those who have an interest in Computer Engineering. He also briefly covers the management style at Bell Labs, which helped to foster the attitude of having a long term view at the Labs; an attitude that probably helped to give rise to Unix.

Chapter two looks at how Unix came about. Multics was originally proposed as a system that could be used by a large group of people at the same time, to be developed by several companies. Unfortunately, it proved to be too ambitious, and Bell Labs decided to pull out of the project. This left the people working on Multics at Bell Labs looking for other things to do. Finding a little used computer, a DEC PDP-7, it was put to use to solve problems and, in the process, Unix was born when the programs were found to be generally useful. One of the main people who would create Unix in a matter of weeks was Ken Thompson, whose biography is provided in this chapter.

Chapter three looks at the first 'official' version of Unix. After the programs and operating system Ken Thompson created proved to be quite useful, an effort was made to convince upper management, who was not interested in creating an operating system after the failed Multics effort, to support Unix. In the end, the usefulness of Unix would win them over, and the group set up Unix on PDP-11 for the purpose of helping Bell Labs produce documents required for patent applications. The chapter also gives an entertaining look at the room used to store the Unix machine and some of the 'fun' they had. A biography of Dennis Ritchie is also provided.

Chapter four skips to the Sixth Edition of Unix produced, which was the first version introduced to the outside world. By then, Unix have proven to provide something unique and interesting to the subject of operating systems: it was portable (able to run on several kinds of processors), a generic file system (unique for its time), a set of language independent system calls, a shell for executing programs and a concept called 'pipes' that would lead to a unique and generic way to chain the input and output of programs. The C programming language would also play a major role in Unix. A biography of Doug McIlroy is provided at the end.

Chapter five looks at Seventh Edition Unix and the huge flowering of work that now grew out of what Unix enabled. This included the Bourne shell, Yacc (Yet Another Compiler-Compiler), the Make system (to manage and build programs from a set of separate files), Troff for typesetting, equation editors, Sed and Awk for text processing, UUCP for copying files from one Unix to another Unix system, and so on.

Chapter six covers other applications and work enabled by Unix. What came before was work done to enable researchers to do their work. Having proven its capability, Unix was now used in the commercial market. One of the first was by AT&T itself, using a Unix front-end machine to manage a disparate group of mainframe computers. Source code control systems was also another application that rose out of the commercial use of Unix. SCCS was the first, but it would enable others like RCS, CVS, Subversion and, currently, Git. The Unix source code was also being licensed to other corporations and universities and out of this would arise various Unix user groups who would band together to support each other and also books that would document and annotate the Unix source code.

Chapter seven is a brief chapter covering the various efforts to commercialize Unix in strange ways, especially over the trademark (TM) and wording of Unix by AT&T.

Chapter eight gives a brief look at the descendants of Unix, which have started to multiply. Systems from BSD to Linux and Plan 9 are covered, but it is not an exhaustive list.

Chapter nine looks at the legacy of Unix, from the various operating systems that arisen from it, to how Bell Labs is now a shadow of its former self, to the recognition the Unix system has given to its designers.

An interesting and entertaining book that looks at a simple question: can be build a dragon? The question is hypothetical, of course, but the book goes through the steps, looking at what we know about biology, to see what would it take to make a dragon, give it dragon features (like the ability to fly and breathe out fire) and, maybe, control it. In doing this, the reader is given an overview of the fields of biology, evolution and genetics. In the end, it may not be possible to build a dragon, but the journey towards creating one as set out in this book is an entertaining one.

Chapter One looks at the kinds of dragons found in mythologies around the world to then decide what kind of dragon to make, namely a flying, fire-breathing dragon. Its temperament and the possible, disastrous effects such a dragon would have on the dragon-making team are also briefly covered.

Chapter Two looks are how to make a dragon fly. Starting with some basic physics (weight versus flight), it goes on to consider which organism might make the best model for a flying dragon, from gliding reptiles and mammals, prehistoric pterosaurs, bats and birds. Various options from feathers to skin flaps are also considered, as well as the genetics of making flight surfaces. Finally, a light-hearted look at how to house a flying dragon are looked at.

Chapter Three covers how to make a dragon breath fire, from how a dragon would generate the fuel needed to breathe fire, to igniting the fire, to making sure the fire doesn't burn up the dragon. A few 'cheats' are also thrown in, like letting the dragon expel chemicals that can burn (like from the bombardier beetle) are also considered.

Chapter Four looks at the brain of the dragon, from how to make one to how intelligent to make the dragon. It goes into some detail on what is currently known about how each part of a brain works and how it affects intelligence, based on research that has been done on brains and on studies on various people who have unusual brains that either have too much or not enough of certain parts of the brain.

Chapter five looks at features that could be added to a dragon, from giving it multiple heads and horns, how to colour it to whether it should be able to shock enemies with electricity. What kind of vision and brain to give a dragon is also considered, as well as a built-in navigation system or even the ability to swim. Whether a dragon should have two or four legs as well as wings is considered, and the ability to spit poison. The ability to also 'shut down' the dragon is also discussed, important in case it gets out of control.

Chapter six looks at how to evolve a dragon. Starting for a particular animal (bird, reptile and so on), genetic changes need to be introduced in order to finally produce a dragon. These changes might be via hybrids or by genetic engineering (introducing or removing genes) possibly by using CRISPR. Cloning is also looked at as a way to 'quickly' produce more dragons, rather than waiting for sexual reproduction.

Chapter seven looks at other creatures that could be produced once we have a dragon. Examples include the unicorn, the flying horse (Pegasus), griffins (and hippogriffs) and merpeople.

An interesting introduction to the elements: from the idea of elements as an ideal form of a material, to the realization that much of the world is made up of many elements. The discovery of several elements, how they become organized and their importance to society and civilization are also covered in this brief book.

Chapter one gives a brief introduction in the history of elements. While Aristotle's idea of four 'elements' is probably well known, the chapter shows it that the elements at the time were considered 'ideal' forms for objects in the work and were made up of mixtures of the elements in different proportions. Metallurgy would introduce a few variations to the idea of such 'elements' before the modern idea of chemical elements would take shape.

Chapter two looks at the role Antoine Laurent Lavoisier would have on the definition of elements. It would surround the discovery and nature of Oxygen. Air was at the time considered an element, but it has become recognized that different 'kinds' of air existed, with differed on whether the air could support life, keep fire alight, be 'bad' for health and so on. Originally, the idea of phlogiston would be used, a supposed substance given off when fire burned. But Lavoisier and others would challenge that idea with an element, oxygen, that aided combustion and would be vital to life. The rest of the chapter would cover the role of oxygen in life, and how it is constantly consumed and created on Earth.

Chapter three looks at the role Gold would play in civilizations. Coveted by many, its very inertness and reluctance to interact with other materials (unlike other metals) would make it precious as a store of value. The desire for gold would lead to advances in metallurgy to extract and purify it.

Chapter four looks at the various ways the now numerous elements are organized. Chemistry would show that the various elements combined in fixed amounts, leading to the idea of organizing them based on their chemical relationships and also their weights relative to hydrogen, the lightest element known. By making and proving (or disproving) assumptions on how atoms are organized, we would eventually get the picture of an atom as one containing a nucleus consisting of protons and neutrons surrounded by a cloud of electrons. Mendeleyev would then become one of the first to organize the elements into a proper table and use it to predict the properties of elements that haven't been discovered.

Chapter five looks at the synthesis of new elements. Radioactivity was discovered and found to be able to transmute elements, changing them into new elements one proton or neutron at a time. But the discovery that some heavy atoms can split into two smaller ones with the release of energy would bring about the atomic age and the nuclear bomb and, later, the ability to fuse smaller atoms together to release even more energy via thermonuclear reactions. It would also lead to a race to create ever heavier elements.

Chapter six looks at isotopes, atoms that have the same number of protons but different number of neutrons. Among the isotopes looked at included Carbon-14 and various isotopes of Uranium and other heavy elements for dating rocks and organisms, and other isotopes that can be used to determine ancient climates via the ratio of isotopes and in medicine by using short-lived radioisotopes that can be detected by medical equipment.

Chapter seven would look at a few elements that have become important to modern civilization: silicon, for producing transistors which, in their billions, are the hearts of computer chips, palladium, which act as a catalyst for many chemical processes and had a role in the infamous 'cold fusion' controversy, the 'rare earths' which drive much of the LCD and related lighting industries and the Nobel gas argon, which plays a role in lamps and in transporting other gases, since it does not take part in reactions and so does not contaminate chemical reactions.

An excellent and hilarious book about the state of actual AI technology in the world (as opposed to the AIs you may see in popular media) and why they can do weird things. As it turns out, the weirdness can be due to the data used to train the AI, in how the AI processes the data and in how we tell the AI to solve a problem for us. You will get a good understanding of how AIs actually work and what they can (and can't) do, and also how AIs can actually help humans do their jobs (or entertain us with hilarious failures).

Chapter one looks at what kinds of AI are featured here. While the public may have some ideas about AI from the popular media, the kinds of AIs looked at here are actual ones in use, which means machine based systems that accept data, apply machine learning algorithms to it, and produce an output. A brief look at how such AI are trained using data and what happens as it gradually learns what kind out output is 'acceptable' is shown. While humans may initially specify what to produce based on the provided input, such AIs may learn and process the data in unexpected ways, leading to weird and unexpected output.

Chapter two looks at what AI systems are now doing. From running a cockroach farm, providing personalized product recommendation to writing news reports and searching scientific datasets, AIs has its uses. The flip side is AI being used to produce things like deepfakes (swapping people's heads or making people appear to do things they didn't). In general, AIs are currently better at very specific tasks (like handing the initial customer support request) and not very good at more general tasks (like creating cooking recipes or riding a bike). One reason is that such general tasks usually require some kind of long term memory to remember what has been done (like when creating long-form essays) but current AIs systems lack this memory capacity. Also, some general tasks create situations that AIs may never encounter in their input training data (like driving safely upon seeing unexpected obstacles).

Chapter three looks at how AIs actually learn by looking at the various types of AI systems: Neural Networks, Markov Chains, Random Forests, Evolutionary Algorithms and Generative Adversarial Networks. Examples of such AIs are given, like the autocorrect system used in smartphones, and their advantage and disadvantages in handling input data, processing it and producing the expected (or unexpected) output.

Chapter four looks at why AIs don't appear to work despite them trying to produce acceptable output. There may several reasons for this: the problem the AI is being asked to solve may be too broad (like making cat pictures after being trained on pictures of people). Or the amount of data provided to the AI may be too little for the task required. The input data may also be too 'messy', full of information not actually required by the task or containing mistakes that confuse the AI.

Chapter five shows how AI complete their task; only it's not the task the designers expected. There are several reasons for this. One is that the AI does the task, only not in the expected way. For example, moving a robot backwards because it was told not activate its bumper sensors (which are located at the front). AIs also usually learn in a simulated environment (to speed up learning), which may lead AIs to exploit 'glitches' in its simulated environment to solve a problem (like 'gaining' energy to jump high by making multiple tiny steps first). Other times, AI solve problems in unexpected ways because the expected learning behaviour is too hard. Like growing a long leg to fall from point A to point B instead of learning to walk (the expected behaviour) as walking is hard.

Chapter six covers more examples of AIs completing tasks in unexpected ways. The main reason for this is that AIs work in a simulated environment, and the solutions it comes up with may only work there. Examples include making optical lenses that are very thick, exploiting mathematical rounding errors or even bugs in the simulation. Such solutions will, of course, not work in the real world.

Chapter seven looks at 'shortcuts' that AIs may take to get the solution. This is usually due to unexpected features found in the training data the AIs may fixate on. For example, an AI trained to recognize a certain type of fish based on images was found to be focusing on fingers in the images instead because in the training data, fingers were always present holding the fish to be recognized. Biases (sometimes hidden) in the input data can also cause the AI to provide biased solutions; for example, recommending hiring only men because in the input data, men were the ones usually hired. Since how the AI comes to a decision is not usually examined, such biased decisions may instead become the norm based on the premise that 'the machine made the recommendation and the machine cannot be biased', not recognizing that bias in the input data maybe the cause of the problem.

Chapter eight considers whether the AI works like the human brain and in general, it is not. AIs have problems remembering things in the long term. For example, passages written by AI tend to meander from topic to topic, generating output that, taken as a whole, is inconsistent. AIs are also prone to 'adversarial attacks' due to it tending to put too much weigh on certain inputs. Examples including modifying an image to mislead an AI recognition program to think a submarine is a bonnet. Or gradually modifying an image of a dog into that of skiers, yet leaving the AI to think it is still looking at a picture of a dog.

Chapter nine looks at the problem of distinguishing between an AI and a person doing a job. This is partially due to hyped up articles that proclaim that AI will be doing certain jobs instead of human (for example, driving). The author provides several ways to probe whether certain output has been produced by an AI or, possibly, a human pretending to be an AI.

Chapter ten looks at the future and shows that the current way forward is a world where both AIs and humans have decision-making jobs to do. AIs can be trained on data, but it is up to humans to determine whether the results are valid and to modify or update the input data to let the AI do a better job. For now, the future is one where both AIs and humans coexists.

An interesting book looking at the Earth at night from space.

It first looks at natural night images of the Earth, as illuminated by natural phenomenon like forest or bush fires, volcanoes, the moon, clouds and lightning, snow and ice, the auroras and atmospheric air glow.

The second section looks at artificial night images, illuminated by urban constructions (cities blocks, factories, refineries) and urban living. Another section looks at before and after images of night views after disasters like hurricanes, wars.

All in all, the book shows a different view of world: how it looks like illuminated at night. It is quite different from normal daylight views of the world as the sources of lighting isn't only the sun, but may be several sources that may or may not follow the contours of the land that can mislead the eye.

There are explanations provided with each image that help explain what the reader is seeing and how to interpret the images, as well as pointing out certain points of interest in each image.

A better than average issue, with interesting stories by Kristina Ten, DaVaun Sanders, Nick Thomas, Jennifer Hudak, and two standout stories by Peter S. Beagle and Aimee Ogden.

• "Approved Methods of Love Divination in the First-Rate City of Dushagorod" by Kristina Ten: an amusing but chilling tale of a country where the family of a girl resorts to 'approved' divination methods to find a partner for their eldest daughter. But repeated divination failures force the daughter to use an unapproved method, which may provide an unlikely end to her quest.

• "Vanishing Point" by RJ Taylor: two explorers on a surface of a planet encounter difficulties approaching what appears to be a gigantic alien. It never appears to get any closer despite their journey towards it. Then, one of the explorers sees a change in perspective that changes everything.

• "The Very Nasty Aquarium" by Peter S. Beagle: an old lady is gifted an aquarium which she then proceeds to decorate with a castle, a mermaid and a diver, along with some fish. But then she makes the unwise decision to add a pirate to it, which sets off a chain of events that may lead to her possession by a very nasty pirate.

• "The Pet of Olodumare" by Joshua Uchenna Omenga and Oghenechovwe Donald Ekpeki: a possibly African version of a creation myth of the universe involving a lonely supreme being who creates a loving pet, lesser beings and then humans. The humans and lesser beings would mess up, and end up creating the world we know.

• "Serenity Prayer" by Faith Merino: a short, mildly horror tale of boys preparing for a hunt.

• "We Go on Faith Alone" by K. S. Walker: a house strangely attracts bird collisions, which may be related to the work a person is doing on green energy that may well cause other kinds of attractions.

• "Little Bird" by Jill McMillan: the story of a girl who used to live alone with her father, and the unsettling outcome of a church gathering that may reveal a secret about what happened to the father.

• "Gather Me a Treasure" by Jordan Chase-Young: a person gathers gifts for an offer to bring back a loved one. But the end result may well be a cycle of gift giving.

• "NPC (or Eight Haxploits to Maximize Your Endgame Farming: A Player’s Guide)" by DaVaun Sanders: people are getting hooked on playing a computer game and doing tasks set by the game in the real world to get more rewards. But it would take one big gathering of material to show who gets the final reward.

• "A Half-Remembered World" by Aimee Ogden: a fantastic story of a city on the back of a giant crab wandering the oceans of the world. But the crab appears to be dying, and so might the city. We learn the lives of the people living on the crab through the eyes of a woman who has already lost much (her child and her companion) but in the end may gain much as the reality of the situation becomes serious.

• "A Meal for Fredrick" by Nick Thomas: a family puts together a paper dragon for fun, but it becomes a permanent fixture in their house. Things take a turn for the fantastic when the father begins 'feeding' the dragon to ward off illness in the family. But it would take one serious illness to break the fantasy of the situation: or does it begin a more fantastic one?

• "The Day of the Sea" by Jennifer Hudak: the Sea, in the form of an old woman, approaches a village and is invited in by one family. Others are not so happy to see the Sea, for in her wake, the seawater steadily encroaches on to their village. But the Sea has lessons on how to survive on the ocean that the villagers eventually accept. The question is whether they learned the right lessons from the sea.

• "What to Do When a Protagonist Visits Your Generic Village" by Dan Peacock: a story of the various possible actions a generic villager can do when a warrior protagonist comes for a visit.

• "Pedestals, Proclivities, and Perpetuities" by Celeste Rita Baker: a lady get tossed on to the roof of a house. Turns out, she enjoys it up there and refuses to come down, eventually setting up a business from up there.

• "A Time to Sing" by Eddie D. Moore: dwarfs warriors face off against giants. The winners will sing of the victory.

• "The Giant’s Dream" by Beth Goder: an artist living inside the body of a giant senses changes and starts to talk to the giant in her dreams; or perhaps she is now appearing in the giant's dreams.