Breakdown of Was für einen Ordner katalogisierst du hier?
du
you (informal singular)
hier
here
was für ein
what kind of
katalogisieren
to catalogue
Questions & Answers about Was für einen Ordner katalogisierst du hier?
Why does it say Was für einen instead of just Was für ein?
The phrase Was für ein is a fixed expression meaning "what kind of", but the ein part must still agree with the case and gender of the noun that follows it. Since Ordner is a masculine noun (der Ordner) and serves as the direct object (accusative case) of the sentence, ein changes to the masculine accusative ending einen.
Does Ordner mean a physical binder or a digital computer folder?
It can mean both! Der Ordner is the standard German word for a physical ring binder used in offices, but it is also the exact term used for a digital folder on your computer's desktop. You would need more context to know whether the person is sorting papers or computer files here.
Since katalogisieren ends in -ieren, are there any special rules I should remember about it?
In the present tense it conjugates like a perfectly normal regular verb, taking the standard -st ending for du. However, an important rule to remember is that German verbs ending in -ieren do not take the ge- prefix in the past participle. If you wanted to use the perfect tense, you would simply say Du hast katalogisiert.
Why isn't the verb earlier in the sentence? Isn't it supposed to be in position 2?