To the Lighthouse is a Modernist novel, which means (among other things) that it's All. About. Style. In fact, many argue that the actual story of the novel itself takes get put on the backburner in favor the form with which it's told. That's one of the hallmarks of Modernist literature: the typical meat-and-potatoes of plot and character sit in the back seat, while previously overlooked aspects like style and structure get to sit up front and drive (if you can even picture that).
So if this book is super-style-conscious, then what kind of style, exactly, does it go for? Well, you don't have to read far to realize that this ain't your typical "Once upon a time" story. It is told from a variety of perspectives, often in a way that be darn confusing for first-time readers. That's because Virginia Woolf was looking to capture what a story looked from inside her character's minds, rather than from an objective narrator's point of view.
As a result, the book has long stretches that record the haphazard workings of human thought. This technique is known as stream-of-consciousness. Why a stream? Well, there's a certain flow to the way thoughts emerge on the page, as one thought suggests another. Like a stream, too, these thoughts don't move in a straight line. They twist and turn, even doubling back on themselves. Check out this example:
Going to the Lighthouse. But what does one send to the Lighthouse? Perished. Alone. The grey-green light on the wall opposite. The empty places. Such were some of the parts, but how bring them together? she asked. As if any interruption would break the frail shape she was building on the table she turned her back to the window lest Mr Ramsay should see her. She must escape somewhere, be alone somewhere. Suddenly she remembered. When she had sat there last ten years ago there had been a little sprig or leaf pattern on the table-cloth, which she had looked at in a moment of revelation. There had been a problem about a foreground of a picture. Move the tree to the middle, she had said. She had never finished that picture. She would paint that picture now. It had been knocking about in her mind all these years. Where were her paints, she wondered? Her paints, yes. She had left them in the hall last night. She would start at once. She got up quickly, before Mr Ramsay turned. (3.7)
If you are just wandering into this passage, your reaction might be to run for the hills. Here, Lily's thoughts bounce around from the lighthouse to Mr. Ramsay to escape, then back ten years, to a picture, to wondering where her paints got to. That's a lot to take in, but it is, we think, an impressive rendering of how our minds work. Let's face it: we don't think "A) Wake up. B) Brush teeth. C) Eat breakfast." Instead, like Lily's passage shows, our minds bounce around. To read that in a novel, though, can seem like stumbling into a dream where we have no clear point of reference.
Our advice? Dive right in. When she wrote this book, Woolf was being boldly experimental with this choice of style, and it's something to savor. Who wants to eat meat and potatoes at every meal anyway?