[murraypaul]

Perhaps it is differences between countries, but coming from the UK, the idea of referring to (state provided) libraries as charities just seems bizarre.
They are government-funded services, paid for out of taxes.
I'm struggling to see a definition that would cover libraries, but not cover the post office, the fire service, the police service, the NHS, and so on.
State-run schools provide free education to all, including the poor. Does that make them charities?
My instinctive view of the word would be that an essential part of a charity is that it is run using funds donated voluntarily.
If you set up your own community library, funded by donations, then that would be a charity.