Bill Bryson is a truly gifted writer, deftly melding facts with wit to expose humorous aspects of the human condition and the world around us.

Therefore, the main literary device employed by Bryson throughout all his work is satire, and A Walk in the Woods is no exception. In A Walk in the Woods, he chronicles hiking the Appalachian Trail with his friend Katz in tow. Neither is really fit or prepared to make the journey, which provides hilarious satirical passages.

He also uses flashbacks to brief the reader on his relationship with his wife and Katz, which gives perspective as to why he is making the trip in the first place and why his connection with his wife is so strong and his bond with Katz is often contentious.

Throughout the book, he touches on his intense fear of meeting a bear or two along the trial, employing foreshadowing as a device to build up to the chapter where he nervously sits in his dark tent one night while bears sniff around his camp.

Lastly, his vivid descriptions of the people and scenery he witnesses along the way bring the reader right with him, seeing, hearing and smelling all his encounters; this creates a strong mental picture through imagery.

Bryson's vivid writing style is conversational, which makes for accessible reading, and this style benefits from his effective use of the literary device of repetition, shown in his use of lists for dramatic effect. Here are but three examples from the beginning of the book:

Already trees are dying in frightening numbers. The elms and chestnuts are long gone, the stately hemlocks and flowery dogwoods are going, and the red spruces, Fraser firs, mountain ashes, and sugar maples may be about to follow.

The woods were full of peril—rattlesnakes and water moccasins and nests of copperheads; bobcats, bears, coyotes, wolves, and wild boar . . .

Then there were all the diseases one is vulnerable to in the woods—giardiasis, eastern equine encephalitis, Rocky Mountain spotted fever, Lyme disease, ehrlichiosis, schistosomiasis, brucellosis, and shigellosis, to offer but a sampling.

As well, Bryson is a master of imagery, and his words create visual pictures and sounds for the reader in the reader's imagination. These examples illustrate imagery:

. . . a sofa-sized boar with cold beady eyes, a piercing squeal, and a slaverous, chomping appetite for pink, plump, city-softened flesh.

I tried to imagine myself lying not in a basement beside the reassuring, cozily domesticated roar of the furnace, but rather outside, in a high mountain pass, listening to wind and tree noise, the lonely howl of doglike creatures, the hoarse whisper of a Georgia mountain accent . . .

Bryson's use of repetition and imagery enhances the reader's enjoyment of the book, as the cadence of Bryson's language brings familiar comforts (in more and more lists, for example) and imaginative flourishes to his descriptions of his experiences in nature.

Bryson writes this novel in 1st person point of view using a casual and enthusiastic tone.  This tone fits the audience - Bryson is not writing for the expert hiker, he is writing for the general public. 

In order to help his audience experience his trip, Bryson uses sensory language.  The example below uses words like "click" and "snuffling" to call upon the sense of hearing: 

There was a sound of undergrowth being disturbed--a click of breaking branches, a weighty pushing through low foliage--and then a kind of large, vaguely irritable snuffling noise.

To assist in the description, Bryson also uses similes:

Once a skunk had come plodding through our camp and it had sounded like a stegosaurus.  

Instantly every neuron in my brain was awake and dashing around frantically, like ants when you disturb their nest.  

Also, Bryson employs humor.  The examples below demonstrate this.  In the first, it is an obvious rhetorical question (certainly the bag has a bottom).  In the second, it is exaggerated comparison - the simple pancakes not versus a bear, but versus a "ravenous..). 

"Are you saying, Dave, that I pay $250 for a pack and it doesn't have straps and it isn't water proof? Does it have a bottom in it?"

It was a perfectly respectable appliance for, say, buttering pancakes, but patently inadequate for defending oneself against 400 pounds of ravenous fur.