The use of "literally" as emphasis, rather than what it actually means. Then I learned that at least one dictionary actually changed its definition to include the idea that literally can also mean figuratively. I wanted to find the source of this linguistic evil and choke it out of them.
I'm also easily annoyed by the phrase "could care less". COULDN'T care less is perfectly sensible, but "could care less" is useless and conveys the opposite point that most people who use it are trying to make. It's such a simple error, I don't understand why it's so common. Similarly, abuse of "much less" and "let alone" is startling common where people get the severity order mixed up (ie. "He couldn't program a VCR, let alone write code for a major company" is the correct use. I'll see people reverse it all the time. Obviously jokes about VCR programing aside).
There are other things, I'm sure.
I'm also easily annoyed by the phrase "could care less". COULDN'T care less is perfectly sensible, but "could care less" is useless and conveys the opposite point that most people who use it are trying to make. It's such a simple error, I don't understand why it's so common. Similarly, abuse of "much less" and "let alone" is startling common where people get the severity order mixed up (ie. "He couldn't program a VCR, let alone write code for a major company" is the correct use. I'll see people reverse it all the time. Obviously jokes about VCR programing aside).
There are other things, I'm sure.