So far, we've discussed a bit how languages change over time; words fall from use, new words are created, and the same words continue but change meaning. I'm not sure that my classmates have bought into this, except in an "old days" or abstract kind of way (as in, 200 years ago "automobile" wasn't a word).
Which of course set me to thinking. When I graduated high school, if someone had said "Google", I would have wondered which Muppet that was. "Facebook" would have been what I did when I tried to read without my glasses. "Access" and "journal" were nouns, and "scrapbook" was a hobby, not an industry.
When I started thinking about words for this post, I marveled at how much the English language has changed in just my adult life. I've always known that languages evolve, of course; one needs only to consider the differences between Portuguese and Brazilian, or English and American and Canadian, or Spanish and ... choose a country. But it's relatively easy to look at those and consider the hundreds of years of separation that have passed-- no wonder they have changed--and harder to see it happen on a day-to-day (or, perhaps, year-to-year) basis.
The first time I went back to visit Scotland, I noticed that the slang was different. Two and a half years passed between my leaving Glasgow and returning, and everyone, not just the kids, was using completely different slang words. This shouldn't surprise me, when I know full well about differences in dialects and regional accents and the fast-changing nature of language-- I didn't need a linguistics class to tell me that-- but it was still stunning when I was face-to-face with the reality of a shifting dialect.
I'm studying linguistics mostly for my own entertainment. I don't intend to make a career of it, but it's a required minor for my Hispanic Linguistics major. And it may prove to be very entertaining indeed.