So, for the record, the Ruy Lopez consists of the following five moves:
1.e4 e5 2.Nf3 Nc6 3.Bb5 ...
I've seen this opening many times, and played it myself many times, without ever knowing that it had a name or that it was the preferred opening of chess officianados everywhere.

One of the
There are many defenses to the Ruy, one of the most popular being the Morphy Defense, basically just attacking the exposed bishop with the A file pawn (3. ... a6), leading to a choice of retreating the bishop (4. Ba4) or taking the knight and losing the bishop. (4. Bxc4 bxc4 ... an exchange favoured by Bobby Fischer, I hear.) I will explore the Morphy defense more deeply next week.
I welcome any advice or comments.