I am a Library Media Teacher. A brand-new Library Media Teacher. An LMT.
Your mother would call me a librarian. Mine does. She has an image in her mind of the kind, old gray-haired lady at Central High School in Duluth, Minnesota. You remember her. I do. Or at least I remember the Covina, California version.
For the most part, those ladies of old (and the vast, vast, vast majority were ladies, and I am no lady!) checked out books, shelved books, decorated the library, and provided a place for students to get books. They did a great job.
I have someone who does that for me. In my middle school library in Fresno, California, I have a full-time library tech. She checks out books, catalogs books, shelves books, works with computers, and much more. I think she's my mother's librarian!
I do some of what she does, to be sure, but I also write grants, develop a technology plan, select books for purchase, teach library orientantion and library research to the entire school, and, in our case, develop a brand-new library program.
Most decidedly not your mother's librarian.