When the CD-ROM era started coming around some of the developers were playing around with the adventure game genre in new ways. One of the interesting first point-and-click graphical adventure games (ala 7th Guest) was The Manhole.
It had the unique concept of no dialogue, nor hints, nor anything but your mouse cursor which you had to figure out where to click to interact with objects on the screen to move around. Basically the pixel hunt you find in most of the adventure games of today.
I was bored to tears by it even though it was one of the first CD-ROM games I purchased; this is coming from someone who played that crummy Sherlock Holmes FMV CD-ROM over and over amazed at the FMV!
In any case here's a screen shot (from the Mac version; the PC version was in color):
The other thing they started playing around with was adding vocal dialogue as well as enchaning the game with true CD audio (none of that lame mp3 music back then). One of the initial graphical adventure games to do this was Loom from LucasArts. Loom was unique in its own way as you had to learn to read music, albiet at a novice level, so you could play it back to cast your spells.
I've tossed you lot a screen shot to help provide a visual aid which will no doubt enhance my spellbinding paragraph above:
So a bit-o expanded history on two other adventure games that are worth a footnote.