Wood can be tricky. For our purposes we are talking about everyday, pedestrian, non-museum quality furniture. If you have spectacular wooden antique furniture in need of cleaning, consult a professional antiques restorer.
For the rest of us, walk this way -- Wood finishes are not all the same. Some wood is finished with a clear polyurethane (permanent), some with shellac (semi-permanent) and some with (short-term finish) none of which are treated equally. (There are other finishes -- polycrylic, varnish, tung oil -- but the three mentioned are the basics and we'll stick with those. There are ways to tell the differences... but take care so as to not damage the furniture piece.
Polyurethane, whether gloss or satin, has a plastic sheen on top of the wood which is mostly impervious to drink spills and food stains -- however, do not sit hot dishes directly onto the wood -- a white hazy stain will likely appear and not recede. Clean with whatever's handy -- polish, ammonia mix, water. Spray and wipe to a clean shine. Polyurethane looks lovely, holds up to heavy traffic use, but once damaged it is not forgiving.
What I like about good quality commercial polishes, like Pledge, is that they work -- they do a nice job cleaning and shining. Occasionally a client will disapprove of a commercial polish because she feels it may cause wax build up. These cleaners don't contain wax -- rather than wax build-up, what they are seeing is the product evaporating -- which means it needs to be polished again. Pledge makes several products, one might be better fit for one particular wood finish over another. Try them to see which one works best for you.
Shellac is a sealer that leaves wood sealed from within, as opposed to on top of the wood. Clean a shellacked piece of furniture with furniture oil, bee's wax or commercial polish like Pledge. If using a wax or an oil, work across the grain, so the polish oozes into the pores of the wood. Remove as much of the excess as possible and wipe, wipe, wipe, shine, shine shine.
A wax finish looks like no finish -- it looks like naked wood. If the surface is very dirty clean it with mineral spirits -- pour mineral spirits onto a cloth and wipe. Re-wax with bee's wax or paste wax, work it into the pores of the wood and buff to a high shine.
When the wood furniture is clean the whole room feels clean. Ahhhh. Enjoy.