The Baker Street Dictionary
A/N: I daresay that this has been done before, but here's my version anyway. I have included some direct quotes from the series, but I also have changed a few of them slightly, and I've added a few bits and pieces of my own. Please do forgive me for any mistakes that you might encounter in the course of the story. Thank you for reading it!
A, B, C, D
A: Army Doctor
The first time that they ever set eyes on one another, Sherlock accurately deduces that John has served as an army doctor in Afghanistan (oh, all right, Sherlock asks John whether it was Afghanistan or Iraq), just by taking one look at the war veteran. John is amazed by Sherlock's observations, instead of being creeped out, unlike so many other people (Read: Anderson and Donovan).
B: Baker Street
To be more precise: 221B, Baker Street. The official dwelling of the only consulting detective in the world, Mr Sherlock Holmes, and his best friend, Dr John Watson. And no, they are not a couple, as John so frequently emphasizes. It's a strictly platonic relationship. John sleeps upstairs, whereas Sherlock's room is next to the kitchen. The refrigerator always contains something unusual, whether it be a human head, some thumbs, or an eyeball. There is a skull in the living room, which happens to be Sherlock's friend, but Sherlock has barely spoken a word to it since John moved in. Sherlock doesn't resort to chatting with it even when John is not around. He prefers to address the air as John, and he fully expects John to hear whatever he says, even when John is halfway across London, or a few hundred miles away in Dublin. A certain Mrs Hudson, who is their charming landlady (not their housekeeper, mind you!), lives downstairs, and takes care of the two boys, even though she is not their housekeeper.
C: Coffee
Sherlock likes his coffee black, with two sugars – a fact with which Molly Hooper is only too well-acquainted. John, on the other hand, likes his coffee with some biscuits, which Mrs Hudson prepares for him, even though (for the hundredth time) she isn't their housekeeper. Sherlock doesn't know how to make coffee very well, and adds far too much sugar whenever he makes a cuppa for John, who doesn't even take sugar. John is always wary about accepting coffee from Sherlock, because he never knows what on earth has been added to it (or to be more precise, what on earth is contained in the sugar), but he gulps down the coffee anyway. Who could possibly resist that (faux) sad face that Sherlock makes when John doesn't drink up?
D: Deductions
Both of the residents of 221B, Baker Street, have blogs. Admittedly, John did scoff at The Science of Deduction when he first came across it, but he has gained more respect for it and its owner since. Seriously, though, what sort of human can tell a software designer by his tie, and an airline pilot by his left thumb? But then again, Sherlock Holmes isn't like any other person on earth. John's blog is by far the more popular of the two (even though the number of visitors is invariably 1895), which irks Sherlock exceedingly. The Science of Deduction is chock-full of logical facts, whereas John's blog has far too much romanticism and emotion in it. 'John, it really isn't necessary to tell everyone that I don't know whether the sun goes around the earth or vice versa. Stick to the plain facts of the case at hand. You may write about how I observe everything around me and make deductions based on what I've seen. Then you may get more readers.' 'Well, Sherlock, I deduce that no one is reading your blog from the fact that you publish posts in which you enumerate 240 different types of tobacco ash!'