What is a shallow face club?

I was reading some reviews on the Taylormade R9 3 wood, and people have been saying it is a "shallow" faced club. What is a shallow faced club, and will it help or hurt a 16 handicapper?

A shallow or deep face refers to how tall the club face is off the ground.

For example, the Callaway FT-IZ has a pretty shallow face for a driver:

Where as the R9 Super-Tri has a deep face:

Yes it is the height of the face.  Generally deep face launches lower and spins less and shallow face will have high launch and spin.   3 woods that are deeper faced are harder to hit off the deck but can add some distance and forgiveness off the tee due to less spin and higher COR (trampoline effect).  SHallow face is generally easier off the deck but not as much distance due to launch and spin (different for slow swingers but this is the internet so I'll skip it).

The trend by OEM's is to make fairway woods that go further.  They do that by making deeper face (also speed slot to add COR) and a longer shaft, both tweaks make the club harder to hit off the ground.

Shallow or deep has a lot to do with your individual swing.

I played with a shallow-faced 3W and 5w (Tour Edge Bazooka Beta-ti) for about seven years. They got the ball up well, and I could get a softer shot with a fade, and a hotter shot with a draw. (The FWs had stiff shafts, however, and switched them out about 2008 when I went back to regular shafts)

A couple of cautions: In fairly deep rough, I popped up the 5W sometimes, almost hitting under the ball (face not very deep).

Also, I had some pop-ups from the tee box. Finally, I started putting the ball on fluffed grass rather than a wooden tee; this prevented pop-ups.

Shallow-face is only one aspect. You also have the clubhead's vertical center of gravity (VCOG) - the lower the more lift - and the shaft characteristics. You'll just have to test one out and see if it fits your game.

The Adams Tight Lie models from the 1990s were the first big-name "low profile" metal woods of the modern era.