I've got a fairly basic problem that I've run up against a number of times
and never satisfactorily solved. Basically I want to fill a column C with the
entries from column A if Column B fills a certain criterion. To give an
example, I want to be able to list in column C all 'Names' that are listed as
'internal' Type-wise.

Name Type Internal External
1 NameA Internal NameA NameB
2 NameB External NameE NameC
3 NameC External
4 NameD Misc.
5 NameE Internal

The Name and Type columns will extend indefinitely downwards; I would also
want to create a column for Misc. and others of course. Ideally I
want to do this without having to resort to using a hidden column for each
Type, since there are very many possible Types. If I do have to use a hidden
column, how would that be done in the best way?

Thanks!