subscribe

Where it comes from

Subscribe ordinarily means to arrange to receive or pay for something regularly, or formally express support for an idea. Subscribe came from Latin subscribere, formed from sub, under, and scribere, to write. It meant write beneath or sign one's name, because assent or obligation could be recorded by adding a signature below a document. The signature became a commitment: one could subscribe to a belief or promise money.

How the meaning developed

Regular payment for a publication followed, and digital services inherited the same model even when the modern subscriber writes nothing.