We are a changeable people, reinventing ourselves almost compulsively.
While any file can be kept viewable or changeable by only you, it can also be shared with whomever you choose to invite.
mid-13c., "unstable, inconstant, unreliable," from Old French changeable "inconstant," from changier (see change (v.)) + -able (see -able). Meaning "subject to variation" is from late 14c. Related: Changeably.