Sometimes it exasperates and sometimes it stings. It's hard to appreciate how many gaps we leave in conversations, taking for granted that that listeners will read the rest between the lines until you meet someone who doesn't.
It's easy to misunderstand people who take things literally. Until you know what the true difficulty is, their reactions can appear insensitive, selfish or disloyal. That's because most of us are so used to dealing with subtexts, we not only assume others will read ours, we are also looking for theirs. Take the following conversation between two friends:
First person: My new boyfriend invited me to a concert for my birthday. Two days before, he tells me that he thought I was buying the tickets because I'm the one who likes that band!
Literal person: So was the concert good?
The first person assumed that her friend would understand the subtext "I was offended that he asked me to pay for tickets he spoke of as a birthday gift and left it so late to tell me." She is then hurt by her friend's response because she sees a subtext saying "You should not be bothered by who buys the tickets and your birthday is not important". But the literal friend only heard a story about the run-up to a concert.
This is the first tip in communicating with someone who takes things literally: join up all the dots and leave no gaps. Especially where emotional reactions are involved, you need to draw a clear line from A to B and explain exactly how one thing leads to another and why. Be explicit, don't leave anything to guesswork. It's not that they will jump to the wrong conclusion as some people might; very literal thinkers don't guess at all.
Another thing to watch for is misleading introductions. If you preface what you want to say with something like "this might be a bit boring but" or "I'm probably overreacting but " the literal person can take it as your true opinion. Instead of the expected "Not at all!" you'd get from someone who knew you were being modest, they could offer suggestions on how to find something more interesting or ways to calm yourself. A similar problem can occur if you broach subjects with a question. "Why did you do that?" is often used to communicate that you didn't like it, but a literal person will think you're expressing interest or curiosity.
Communicating with literal thinkers might take a bit of extra work in the spelling-it-all-out department but they require less caution and diplomacy than highly sensitive friends. With literal people you might be "non-understood" but you're at less risk of being judged or criticized for a careless remark. Because they don't read so much between the lines, you won't have to spend undo time soft-soaping, apologizing or smoothing ruffled feathers. As long as you say what you mean and mean what you say, there should be little cause for regret.
It doesn't take long to form a communication bridge with someone who takes things literally, and once built it tends to last. After that, you might even find that your literal friends are some the easiest people to be around as they are as unlikely to embed hidden meanings as to see them.