Viewfinder
The Canon PowerShot SD990 IS has an optical viewfinder for those who prefer to frame their shots at eye level. It's just a small window in the plastic without any padding for comfort. As it's an optical viewfinder there's also no overlay or information when you look through it, so any adjustments you make will have to be verified on the LCD display.

An optical viewfinder is available for those who prefer
to directly eyeball the situation.
LCD Screen
The Canon PowerShot SD990 IS sports a 2.5-inch LCD display with a resolution of 230,000 pixels. It will get the job done, but no one is going to be wowed by it.

The 2.5 inch LCD display is nothing special.
Flash
The flash on the SD990 IS sits above and to the right of the lens on the front. This close placement means that you're probably going to be contending with red-eye in dark rooms where you need to flash in the faces of your family and friends.

The flash is very close to the lens.
Lens
The Canon PowerShot SD990 IS has a 7.7mm - 28.5mm, f/2.8-f/5.8 lens that supports 3.7x optical zoom. The lens retracts into the body of the camera when it is off, making it much easier to carry around.

The lens retracts fully into the body when the camera is turned off.
Connections
The only port on the whole Canon PowerShot SD990 IS is found on the right side under a tethered plastic cover near the top. Remove the cover to reveal the mini USB port that doubles as an A/V out.
The Mini USB port is used for both data transfers and A/V out.
Battery
The Canon PowerShot SD990 IS uses a proprietary battery. Canon rates the battery for 280 shots using the LCD or 700 shots if you use the viewfinder instead.
Battery and SDHC card slot both sit under the door on the bottom.
Memory
The SD990 IS supports SD and high-capacity SDHC cards, currently available in sizes up to 32GB. The memory card slot is found right next to the battery, behind the same slide-out door..