If you intend to camp in Namibia, then your choice of equipment will be affected by how you are travelling; you'll have more room in a vehicle than if you just carry a backpack. A few things to consider are:

Tent
Mosquito-netting ventilation panels, allowing a good flow of air, are essential. Don't go for a tent that's small; it may feel cosy at home, but will be hot and claustrophobic in the desert. That said, strength and weatherproofing are not so important, unless you're visiting Namibia during the height of the rains.

Mat
A ground mat of some sort is essential for comfort, warmth and protecting the tent's groundsheet from stony ground (put it underneath the tent). The ubiquitous closed-cell foam mats are good and readily available. Genuine Karrimats and Therm-a-Rests (combination air-mattress/foam mats) are quite expensive, but much stronger and more durable – worth the investment.

Sleeping bag
A three-season down sleeping bag is ideal, being the smallest and lightest bag that is still warm enough for winter nights. Synthetic fillings are cheaper, but for the same warmth are heavier and more bulky. They do have the advantage that they keep their warmth when wet, unlike down, but clearly this is not so vital in Namibia's dry climate.

Sheet sleeping bag
Thin pure-cotton sheet sleeping bags (eg: YHA design) are good protection for your main sleeping bag, keeping it cleaner. They can, of course, be used on their own when your main sleeping bag is too hot.

Stove
'Trangia'-type stoves, which burn methylated spirits, are simple to use, light, and cheap to run. They come complete with a set of light aluminium pans and a very useful all-purpose handle. Often you'll be able to cook on a fire with the pans, but it's nice to have the option of making a brew in a few minutes while you set up camp. Canisters for gas stoves are available in the main towns if you prefer to use these, but are expensive and bulky. Petrol- and kerosene-burning stoves are undoubtedly efficient on fuel and powerful – but invariably temperamental, messy, and unreliable in the dusty desert. If you're going on a long hike then take a stove and fuel, as firewood may not always be available in the drier areas.

Torch (flashlight)
This should be on every visitor's packing list. Find one that's small and tough, preferably water- and sand-proof. Head-mounted torches leave your hands free (useful when cooking) but some people find them bulky. The small, strong and super-bright torches (such as Maglites) are excellent, but their bulbs are difficult to buy in Namibia. Bring several spares with you.

Water containers
For everyday use, a small two-litre water bottle is invaluable – however you are travelling. If you're thinking of hiking, you should bring a strong, collapsible water-bag for times when you will be away from a close source of water. Ten litres is a useful size, and probably the most you'll ever consider carrying on top of your normal kit. (Ten litres of water weighs 10kg.) Large plastic containers for the car can be bought when you arrive.