I had a brief (15-20 minutes ) discussion with a Human Resource Manager who introduced the Company and had me present myself.
I was told that the details about the job opening would be explained by the Department Manager (I had applied for an engineering position on the website).
After an interesting chat with the Department Manager, who provided more details about what the Company and their job, I understood that the interview was about a similar named position and not the Engineering position I had applied to on their website.
While the interviewing process was straightforward and polite, it would have been nice to find out the details before the actual interview.