As other have said, typeglobs are globals. If you're comfortable with that, then this will get you started on how to assign to, and dereference them:

 our *a = \25; *a = [1..10]; *a = { 'a'..'z' };;

printf "Scalar:%s\nArray:[ %s ]\nHash:{ %s }\n", $a, join(',', @a ), j
+oin('.', %a );;
Scalar:25
Array:[ 1,2,3,4,5,6,7,8,9,10 ]
Hash:{ w.x.e.f.a.b.m.n.s.t.y.z.u.v.c.d.k.l.q.r.g.h.i.j.o.p }

printf "Scalar:%s\nArray:[ %s ]\nHash:{ %s }\n", ${*a}, join(',', @{*a
+} ), join('.', %{*a} );;
Scalar:25
Array:[ 1,2,3,4,5,6,7,8,9,10 ]
Hash:{ w.x.e.f.a.b.m.n.s.t.y.z.u.v.c.d.k.l.q.r.g.h.i.j.o.p }
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Of course, that's only three of the six things that can live in a typeglob; but I'd have to look the others up as I've rarely used them.

If you want the full skinny on them, see MJD's page on them.