Tag Archives: book

Book Review: How Software Works

Another month, another book kindly sent for review from No Starch. This one’s of the more conceptual variety, and sets out to explain – in laymen’s terms – the algorithms that are responsible for much of the “magic” of modern technology.

hsw_cover-front

When I was younger, and just getting into computers, I used to spend hours reading second-hand software and hardware manuals. I think I must have read the manual for my old computer’s motherboard 50 times. A kindly network engineer from the PC Pro forums (ah, those were the days) sent me an old 400-page networking manual that I inhaled too. Manuals were the best. Manuals showed me what computers were capable of.

It wasn’t until later that I became aware of where the real action is. Algorithms. Manuals are a fine thing, but they’re typically written at a high-level. They tell you what’s happening – and which buttons to press – but, for expediency, often skip over the “how” – the way the mysterious feats that first got me fired up about computers are actually achieved.

This book, How Software Works (by V. Anton Spraul), is all about the “how”. You won’t find any practical manual-type information in here at all, so don’t expect to come out the other side of this book with a finely-honed knowledge of printer troubleshooting or anything like that. No, this is a very pure book that explains, in uncompromisingly non-technical terms, how computers achieve their magic.

Each chapter covers a broad but real-world relevant topic, such as web security, movie CGI, or mapping. After some background on each topic, Spraul sketches out the most important pieces of the algorithmic puzzle needed to produce the “everyday” results we now take for granted in movies, on the web, and in our smartphone apps. This might include a walkthrough of the logic behind a trapdoor function, of the sort that that makes public key encryption possible (which in turn makes internet shopping practical). Or perhaps the step-by-step process by which a rendering program builds up a realistic virtual scene in a movie, through ray tracing.

The writing is very clear and non-technical, almost without exception, and assumes very little prior knowledge. You do not need a technical background to understand this book, but you’ll want to spend some time to follow the examples and ruminate on them a little to really get everything. The examples themselves are plentiful, and include step-by-step illustrations of simplified situations that, when linked together, demonstrate how each algorithm works as a whole.

Given that this is a book on software, it’s slightly disappointing that the presentation is completely “dead-tree traditional”. By this, I mean that there’s no supplementary material in the form of working code snippets that one could play with, or interactive demonstrations. This feels like a missed opportunity, at least for those of us who learn best by tinkering (c.f. the excellent W3Schools “Try It Yourself” tutorials). It’d also turn the book into a more direct educational tool, perhaps something that a class could be based on – and there are enough simple web-based programming systems out there to remove much of the burden of having to “teach” programming in the first place. This is more of a wishlist item than a crucially missing piece, however.

Another minor criticism is the length of the book. It would have been nice to see a few more topics covered, or perhaps a little more detail in the final chapters. The material on searching could go into more detail in explaining how web search works, for example, including things like how robots/crawlers and ranking algorithms (e.g. PageRank) actually do their thing. As it is, it feels like the author ran out of steam before getting to the real crux of this topic.

All in all, it’s a very nice book, and I learned a lot about some interesting, highly-relevant techniques that I was only dimly aware existed. The material on encryption in particular outlines a clever and essentially mathematical topic that will speak to those of you who enjoy logic puzzles, for example. I’m not quite sure who the intended audience is for the book as a whole, but it’s definitely something to keep in mind for an aspiring techie – a teenager who’s still reading the manuals, perhaps, and is ready to have their horizons broadened. The mechanically-minded, those with a fundamental curiosity about how things work, will also enjoy.


Book Review: How Linux Works 2

I received a review copy of How Linux Works 2, by Brian Ward, from the lovely folks at No Starch Press (my publisher) late last year. Inexcusably, it’s taken me until now to put together a proper review; here it is, with profuse apologies for the delay!

How Linux Works 2

How Linux Works 2 is a very nice technical read. I’ve been a user and administrator of Linux systems for over a decade now, and can safely say I learned a lot of new stuff from both angles. Newer users will probably get even more from it – although absolute beginners with less of a technical bent might be better off looking elsewhere.

The book fills something of a niche; it’s not a standard manual-type offering, nor is it a technical system reference. It’s more impressionistic than either of those, written as a sort of overview of the organisation and concepts that go into a generic Linux system, although with specific details scattered throughout that really get into the nuts and bolts of things. If you’re looking for “how-to”-type instructions, you’re unlikely to find everything you need here, and it isn’t a comprehensive reference guide either. But if you’re technically-minded and want to understand the essentials of how most Linux distros work in considerable (but not absolute) depth, with a bit of getting your hands dirty, then it’s a great book to have on your shelf.

Various technical concepts are covered ably and concisely, and was I left with a much better feeling for more mysterious Linux components – like the networking subsystem – than I had before. There are practical details here as well though, and you’ll find brief, high-level overviews of a number of useful commands and utilities that are sufficient to give a flavour for what they’re good for without getting too caught up in the (often idiosyncratic) specifics of their usage.

That said, the author does sometimes slip into “how-to” mode, giving more details about how to use certain tools. While this is fine in moderation, the choice of digression is sometimes unusual – for example, file sharing with Samba is awarded a whole six pages (and ten subsections) of usage-specifics, while the arguably more fundamental CUPS printing subsystem has to make do with less than 2 pages. The discussion of SSH is also quite limited, despite the importance of this tool from both the user’s and administrator’s perspective, and desktop environments probably could have done with a bit more than a brief single-chapter overview. Still, this book really isn’t intended as a manual, and the author has done well not to stray too far in this direction.

A common difficulty for Linux books is the great deal of variation between distros. Authors often struggle with where to draw the line between complete (but superficial) distro-agnostic generality and more useful, but audience-limiting, distro specifics. How Linux Works succeeds admirably in walking this tightrope, providing sufficient detail to be useful to users of more or less any Linux system without repeatedly dropping into tiresome list-like “distro by distro” discussions. This isn’t always successful – the preponderance of init systems in modern distros has necessitated a long and somewhat dull enumeration of three of the most common options, for example – but HLW2 does much better at handling this than most books I’ve seen. The upshot is that the writing is fluid and interesting for the most part, without too many of the “painful but necessary” digressions that plague technical writing.

Overall, this book is an enjoyable and informative read for anyone interested in, well, how Linux works! You’ll get an essential understanding of what’s going on under the hood without getting bogged down in minutiae – making this a very refreshing (and wholly recommended) addition to the Linux literature.

You can find a sample chapter and table of contents/index on the No Starch website.


Book review: Think Like a Programmer, by V. Anton Spraul

My publisher, No Starch Press, sent me a review copy of another of their books a few months ago. Regrettably I’ve been a bit slow in getting around to properly reading it, but here, finally, is my review of Think Like a Programmer, by V. Anton Spraul.

Front cover of Think Like a Programmer

Programming is as much an art as it is a science. When you’re starting out as a programmer, there’s a big mess of concepts and rules to get into your head before you can do anything much more complicated than printing out a shopping list on-screen – things like differences between different types of variable, and how pointers work. Even if you’re dealing with a language that hides all of these icky details, like Python, you’re still going to find yourself spending most of your time learning about specific structures like for loops or class declarations.

Most books for the newbie programmer focus on these mechanical details, generally with specific application to only one programming language. And quite rightly so, in my opinion; after all, it’s only by learning this stuff that you’re ever going to be able to do anything interesting. And so it’s only when you start programming regularly, or try to do anything more substantial, that the “artistic” side of programming starts to become really important.

With Think Like a Programmer, Spraul has his sights firmly set on the people who’ve already put the time in with the initial “science” bit. They have a decent amount of experience with one, maybe two, programming languages, and have progressed beyond textbook exercises or copy-pasting together code snippets to actually writing their own functioning code from scratch. But it’s at this point that a lot of people get stuck, with some of them never moving far beyond this predominantly mechanical understanding. Without a firm push in the right direction, habits can develop, experience reinforces them, and the art of programming never blooms.

It’s a philosophy, not a cookbook

Think Like a Programmer is a 233 page push in the right direction. It’s not a pattern book, with endless lists, block diagrams, and flowcharts for deciding when to use one tried-and-tested program structure over another. It’s not a cookbook, with myriad clever, practical examples to use as “inspiration”. Nor is it an “advanced programming” textbook, with detailed treatises on using the obscure, God-level features of whatever programming language you’re most concerned with. No. While it does have elements of all of these things here and there (they’re useful, after all), it’s much more concerned with your attitude to programming – how you approach solving problems with code. Your coding philosophy.

It would be easy to churn out a book on this subject that goes little farther than chastising you into adopting good coding style (how to indent blocks? where to add comments? how to name variables?), and pointing at a few useful patterns that relative newcomers often don’t know about. But Spraul has gone far beyond this. He starts off with a general discussion on how to solve problems, using examples of the type you might find somewhere near the back of a newspaper. The puzzles he walked through were really fun, and it felt good to go from blindly fiddling around with them to successfully applying the strategies he suggested. The lesson he’s teaching here is to sit down, think about the problem, and start using powerful general-purpose approaches like reducing it into smaller sub-problems, being systematic, and so forth. And, hey, whaddaya know? It works. Thinking works!

It’s a journey, not a destination

Things progress from there into the programming domain. In each successive chapter, Spraul builds on the discussion that has gone before, introducing new, generic, problem-solving approaches and combining them with the methods discussed previously to solve progressively harder example problems. The examples are followed through in excellent explanatory detail, with an emphasis on the structure and logic behind the code rather than the particular language features that are used (though all the examples are in C++, which has its fair share of relatively opaque syntax). He also strongly encourages that you try the numerous exercises at the end of each chapter to cement what you’ve learned, an approach that, while it may sound dry and textbooky, really does help you to get to grips with things.

There are chapters on general programming/problem-solving approaches, plus more specialised ones on using important tools like arrays, classes, pointers, and recursion to your advantage (the recursion one is available to download for free). The discussion is kept general – there’s little in here about specific optimisation or debugging tricks, and rather more of an emphasis on just writing good code, regardless of the specific application you might have in mind. As such, if all you’re after is quick tips for making your code run better, you’re not going to get that much out of the book. If you’re willing to sit down and patiently follow it through, however, you’ll find that what it’s teaching you is an enlightened approach to programming – essentially, how to become a Good programmer with a capital-G. And in the long run, that’s what’s going to make the difference between scraping by, writing cobbled-together solutions that just about work, and outputting truly nice, effective ones.

That troublesome audience

This is all well and good – noble, even – but I can’t help but wonder if the book will get through to its intended audience. If a novice programmer picks this up, there’s a good chance that they’ll struggle with the choice of language. While it’s a sensible pick for showing off the concepts the author is interested in, C++ isn’t the easiest language in the world, and Spraul isn’t afraid of using some of its more obscure syntax with only the briefest of explanations. For someone with experience only of Python, for example, the one-page overview of how pointers work in C++ isn’t going to leave them much wiser on the subject. There’s absolutely nothing to help the non-C++-using reader get set up with compilers and IDEs either, which could cause some serious headaches for those actually wanting to play with the examples themselves. As a result, those familiar with C++ will find the book a considerably easier ride than those who are not, which is a shame.

The purpose of the book is also a bit more subtle than your average (the blurb describes it as a “one-of-a-kind text”). You know what you’re getting with a cookbook, whereas the benefits brought by Think Like a Programmer are somewhat less tangible. The readers who’ll get the most out of this are the patient, motivated learners, whereas those who’re looking for shortcuts and quick fixes to “becoming a better programmer” will likely find it frustrating. Ultimately, I guess that’s fine – you can only help those who will be helped – but I guess this sort of presentation would be more effective to a broader range of people  in the context of a taught course rather than self-study.

Verdict

The book is well-written, with tons of excellent advice and solid, well-thought-out examples. If you’re willing to devote some time to studying the material (perhaps, depending on your background, with a C++ reference in hand), you’ll soon find yourself equipped with an impressive array of problem-solving strategies and, maybe, a new outlook on programming. Recommended.


Book review: The Artist’s Guide to GIMP

I just reviewed The Artist’s Guide to GIMP over at my open source blog. Overall, it’s a nice introduction to the free image editing powerhouse that is the GIMP – the book is packed full of interesting projects that seem pretty easy to follow, written in a refreshingly waffle-free manner. It would make a good read for web developers, computer artists, and Photoshop whizzes interested in moving over to the right side of the proprietary software divide alike (although the bits on photography have some rough edges).

See here for the full review.


Book review: The Linux Command Line, by William E. Shotts

No Starch Press kindly sent me a copy of The Linux Command Line to review a little while back. I already posted a review on Amazon, but figured that the book might be of interest to people here, too. Read on for a fuller, more detailed review.

The Linux Command Line book cover

Although point-and-click graphical interfaces may initially seem more intuitive, many tasks are much better suited to command line applications. I first started using the command line mostly out of necessity, back in the days when desktop Linux was still rather unfriendly to new users. After a little while, I had gained enough familiarity with the system to start cooking up useful combinations of commands for myself, without having to constantly copy them from books or webpages. I soon found myself preferring to use the command line for many tasks – it became quicker and easier than using a GUI. I even gained a rudimentary understanding of how the command line itself works, and started using a few of its more advanced features. And that’s the stage I’m at now – I know how to use a range of useful commands, and can achieve a lot using the command line in an efficient and satisfying manner. But anything beyond the basics of powerful concepts like regular expressions, commands like sed and find, and the ins and outs of Bash scripting, are still a bit of a mystery to me. If I need to do anything fancy, I fall back on doing it manually, or else write a Python script, simply because I’m more comfortable doing things that way. “The Linux Command Line” is a very useful book, in that it has helped me to take my command line skills to the next level, making it much less of a necessity to develop my own tools.

Something for every eventuality

As with most books from No Starch*, the book is beautifully presented and well written. All of the common command-line tasks are covered, many of them in detail, and there are a number of nice, friendly introductory chapters (pdf) for those who have never used a command line before. But the real value, for me at least, came from the treasure trove of more obscure commands that the book contains. UNIX is a very mature system, and practically every computer-based task you can think of can be performed using existing command line tools. Indeed, on first opening the book to a random page, I immediately found a tool to automatically format text files in a rather specific way, a task that I had been wasting quite a bit of time doing manually (and hadn’t yet encouraged myself to automate). Even old hands will be able to find something new in here, such is the diversity of the topics covered.

Other highlights include a guide to programming in Bash, which cuts through the quirks of the scripting language in a rather transparent manner, and a number of chapters on the common system admin tasks that occupy most peoples’ command line time. The latter part is slightly hampered by being rather distro-specific in places, choosing only to cover Debian (Ubuntu) and Red Hat (Fedora) where non-generic commands must be used. A couple of other distros could have been added to the list without too much fuss, allowing the book to serve as a useful cross-distro reference.

Covering all the bases

And that brings us to one of the difficulties with books like this: Completeness. The cover’s promise of a complete introduction is a bold one, and Shotts can be forgiven for not providing a comprehensive guide to every last command; there are just so many of them, and they can get quite complex. Nevertheless, there are some interesting omissions here. Terminal-based text editors are extremely advanced, offering real productivity gains for programmers and other would-be command line users, but they go largely unmentioned. While a comprehensive introduction to emacs is certainly outside the scope of this book, it could at least have been mentioned! Only a brief introduction to vim is included, which suffices for basic text editing tasks. Additionally, important networking tools like SSH, which are vital for remote working and system administration, are covered only very briefly. In an ideal world, I would have liked to have seen a whole chapter with detailed information on SSH, tunnelling, and the like. This lack of total completeness, understandable though it may be, will leave some readers a little disappointed. Still, the majority of topics are covered in suitable depth to satisfy the majority.

It’s probably best to treat this book as an advanced introduction – reading it will introduce you to a whole range of useful tools, which you can then go on to learn more about using specialised documentation, or more focused technical manuals. The Linux Command Line will get you started, and quite a lot more, but you’ll eventually need to move to something more specific if you really need to delve into the murkier recesses of a certain command.

Verdict

If you would like to start using the command line, improve your existing skills, or simply want to discover tools that you were never even aware existed, this book has everything you need, and I wholly recommend it. If you want to learn about the specifics of some particular command line tool, you’ll at least get a good introduction here, but you’ll eventually have to read its manual all the same.

* Including my own; I’ve authored two titles with them, and love the house style to pieces.