To the camera experts in the house!

An SLR, single lens reflex, camera of any king, digital or not, is one that has a prism/miroor system that sends the light from the lens up to the viewfinder so when you look through your are seeing what the camera sees.

The SLR is quite a bit more versitile and expensive than a 'point and shoot' style of camera.

Some of the advantages-- which you may or may not value -- of an SLR include:

• Interchangeable lenses.  You can get specialized 'macro' lenses for extreme closeups, or wide angle lenses, or telephoto lenses.  These lenses can have quite a bit better resolution than a point and shoot's lens.  The SLR lenses usually are 'faster' -- meaning that they let in more light; you won't need to use flash quite as much.  This also allows you more control of 'depth of field' -- the part of the picture in focus.  You can go for having everything in focus, or only part of the subject in focus.
  
• More flash options.  Many digital SLRs have a point-and-shoot type flash built in.  You can also use off camera flash, bounce flash, shoot through an umbrella (softer light and shadows), use multiple flash, etc.  The seperate flashes are also a lot more powerful than the ones on point and shoot cameras, giving you more 'range' on your flash shots..  Point and shoots have just a single weak flash pretty close to the lens which usually results in a red-eyed, pasty-skinned flat picture (if people) or glaring 'hot spots' if taking pictures of something like a model.
  
• You can keep your investment in lenses when you 'trade-up' bodies. 
  
• Better located, sized, and shaped controls, and better access to the controls the camera offers.   Controls on a point and shoot have to be small in size, limited in number, etc.  That means that you might have to hunt around on a point and shoot to find a control that is just a button press away on a SLR.
  
• Usually better, faster auto-focus
• Smaller delays between shots
• Higher resolution sensors
  

Downsides of an SLR include:

• More expensive
• More complex
• Larger
  

Bottom line -- if you are *serious* about photography, you should consider a SLR.  If you just want to get the picture and not have to futz with a lot of things, buy a point and shoot.  I own and use both.

Recommendation -- if you're seriously looking at taking pictures of your work that show your model to the best advantage, an SLR is the best way to go.  But you will spend more.  And since there are a lot of accessories for SLRs, you will find more things to spend money on.  Believe me, I know.

  -- Bill