Konstantinos Michailidis‘ and Alex Giannakakos‘ answer are the same. Kritharaki is Risoni (Orzo (pasta)), and Giouvetsi is meat with risoni.
On Stella pasta’s web site (Stella – Μακαρόνια), their risoni is advertised as Φτιάξτε ονειρεμένο γιουβέτσι για όλη την οικογένεια και πείτε «Stella κύριοι! Σας μιλάω εκ πείρας!» (“Make a dreamy giouvetsi for the whole family and say ‘Stella gentlemen! I speak from experience.'”) (“I speak from experience” is the slogan at the start of the poster.)
Love giouvetsi…