These icons represent a selection of possible data types that an
individual might want to use to represent hir identity. Other possibilities
might include reputation scores, archived communication logs, social
network, movies or digital fashion items. Generically, we assume
that an individual could create a generic file and point it to any
type of data or information.
In some cases, it might appear as though a data type is too broad
(i.e. phone). Shouldn't you want to specify home phone versus cell
phone? One might want to just leave an appropriate phone number
and then control from there where it goes to.
Regardless, the types of information that one can convey should
be broad and extensible, allowing the user to control what represents
them, not the system.