The lesson I’ve learned from a career in writing is that there are only three kinds of books that authors write: arm stretchers, retina wreckers, and hair pullers. Because it’s not what books are about, but what it takes to write them.

I have written a dozen books covering all sorts of subjects and ranging from short to encyclopedic lengths. A couple of them took just under a year to write, and others took several years. Almost all were published by the major houses. With this range of experience, I have come away with my own views on the trials and tribulations of shaping words into book-length prose.

An arm stretcher is a book in which not a huge amount of effort is needed. I won’t say it’s a breeze to write, because I don’t think any book-length work is a cruise down the river. But an arm stretcher—so named because after each writing session the author should smugly stretch out his or her arms as if to say, “Oh, I love the writer’s life”—is a relatively easy endeavor as book writing goes, which is to say you’re only climbing Mount Rainier instead of Mount Everest.

An arm stretcher may not require gobs of research or years of toiling in the trenches, so some authors are always on the lookout for ideas that would make for an easy book—you know, just to fit them in every once in a while between the retina wreckers and hair pullers. Literary novels certainly don’t fit into this category, nor do full-length biographies, ancient histories, or multivolume encyclopedias.

Retina wreckers involve tedious writing and research day after day, month after month, sometimes for years, and can leave a weird residual effect on eyeballs. These books require painstaking verification of facts, tremendous organization of thoughts, fastidious construction of sentences, and more rewriting and polishing of sentences than most readers would imagine. The hazards of writing a retina wrecker are that it can leave the author bleary-eyed, or if the author wears corrective lenses, it can result in a change of prescription (and not for the better).

Hair pullers should be avoided like the bubonic plague, unless you get an eight-figure advance or are desperately out to prove something to the world. They’re four retina wreckers rolled into one, and they can do you in. They take so long to write that you become a hopeless prisoner of the word trade, unable to imagine the day when you’re set free. They drain you, take a toll on you, become an obsession. You eat with them, walk with them, take them to bed with you. They jeopardize your sanity. When you’re writing one of these, you forget what it’s like to have a real life. Having fun, oh, that’s just a memory. They can cause you to develop neurotic tendencies such as twitching, blinking, or pulling the hair out of your head.

What all these types of books have in common is that they’re mirror grabbers. You are curious about what you look like. Do you still have your hair? Are you able to smile? How are your teeth? Any more wrinkles? So you reach for your pocket mirror. You look, you inspect—you may even want to have a conversation with the only person you know who understands you, so you talk to your image in the mirror.

And yet with all the hardships in writing books, there’s no question as to why writers relentlessly ply away at their trade. Of course, other authors understand, but not all civilians do—civilians referring to spouses, children, relatives, friends, neighbors, and acquaintances who think we’re gluttons for punishment, since they just don’t get that creating is something we have to do, regardless of the economic return. Because we not only love to write, but we have a glimmer of hope that our work can bring joy to people, or educate them, or help them in some way, or even change the world.

Writing can surely be hard and laborious, but as writers, we’re willing to do whatever it takes to get the job done.

Harvey Rachlin is a lecturer at Manhattanville College in Purchase, N.Y.