Tier 1 consists of the objects that extend Tcl, and can be used in a tclsh without loading Tk, if desired (set ::env(POET_TIER) to 1 before loading the Poet package). The most important object is Object, the ancestor to all Poet objects. You should read the documentation on Object before attempting to program in Poet. The object Poet
allows some control over the inner workings of Poet, and is required
reading for advanced use. The rest of tier 1 provides the
persistence support (Thing and ThingPool) and assorted utilities.