If, like me, you have a lot of books, you'll need to find a way of organising them. Ideally, you'll do that in a way that makes it easy to find what you want where you want it. I said "ideally" -- it doesn't always work out like that, and besides, there are other ways too.
Books, by Marisa Sias CC0
An excellent article on this subject is by Hannah Gersen. Entitled 10 Ways to Organize Your Bookshelf, it contains some quirky and interesting suggestions. It's well worth a read, but it's not exhaustive. Based on my own experience, here are three more approaches.
By size
This is a fairly impractical method because before you can find a book you have to try and remember how big it is. My wife and I were forced into this position when we married and moved into a new home together, because my father-in-law, an amazing handyman at the time, offered to make us some built-in bookshelves.
Some of these had large gaps between them, and others had smaller gaps between them. So we had to stack our books according to where they would fit on the shelves. Even today, we still have the occasional conversation like this:
"Do you know where <name of book> happens to be, as I fancy reading it again?"
"Erm, can you remember how big it is?"
By room
As our finances and book collection have expanded, without a concomitant increase in the room available on those original bookshelves, we've had to house a growing number of books in different rooms.
The best arrangement we could come up with, which tends to be pretty fluid, is as follows:
Books we happen to be reading at bedtime: in the bedroom (duh!)
Books we think we ought to be reading and which we will definitely get around to soon: in the living room.
Books that are required for work purposes: in my case this means that books about writing, grammar, style etc, plus books I have to be review, live in my study.
This has added a new frisson of excitement to our book searches: in addition to trying to recall how large a book is, we have to try and remember which room we last saw it in.
Virtue (or other) signalling
I don't do this, but a colleague who came round for dinner once accused me of doing so. The idea is that you carefully display 'publicly' those books you think will make a good impression on your guests.
So I guess if you invited your boss around for dinner you'd hide books with titles like 'How to manage your boss' and substitute ones with titles like 'How to improve your efficiency'.
(This isn't new, of course. Eons ago Mad Magazine featured special paperback covers with erudite-sounding titles that you could slip over the books you were actually reading, in order to make a good impression on other passengers on the subway or tube. Also, I recall visiting an old house once, and in the library were loads of interesting-looking books -- or so I thought. Many of them turned out to be theatre props, ie wooden planks with book covers printed on them!)
The approach doesn't much appeal to me, I have to say. Apart from the basic dishonesty (in my opinion), it sounds like an awful lot of work.
I must say, however, that no matter how much I try to keep my book collection organised, I have discovered that it, too, is governed by the universal law that states that any system will tend to descend into disorder over time. In other words, the plaintive cry "Have you seen <name of book>?" is a fairly common one in our house.
But it's not for want of trying.