-Mailing lists at MIT come in too varieties --- Moira and Mailman. Moira lists don't have spam filtering, moderation, built-in archiving, or a number of other features. Mailman has far more features, but mostly requires administration through a web interface (which many people dislike) and Mailman lists cannot be used for access control (in AFS, or to own other lists).
+Mailing lists at MIT come in two varieties --- Moira and Mailman. Moira lists don't have spam filtering, moderation, built-in archiving, or a number of other features. Mailman has far more features, but mostly requires administration through a web interface (which many people dislike) and Mailman lists cannot be used for access control (in AFS, or to own other lists).