Why "ordinary"
Most library writing online is either a glossy case study or a technical manual. This is neither, it's the actual, ordinary week-to-week of the job, written honestly.
The logo, explained
The porthole is the frame this whole site looks through, a small, honest window rather than a wide, polished one. The book inside it is the actual work, not the idea of it. The waves underneath are just the ordinary tide of the job: the part that keeps moving whether or not anyone's writing it down.