Sources of artifical light can produce various washes in your color photographs; it is important to be aware of the effects produced by different kinds of light so you can either use them to your advantage or avoid them altogether.

Most indoor household bulbs give off tungsten light and lead to yellow-colored photographs. This is not necessarily a bad thing; many photographers (Nan Goldin, for one) have used this effect wisely and purposefully - it can add emotional overtones to your photographs ranging from warm and welcoming to dank and ancient. However, if you don't want the yellow overtones, this can be compensated for in the darkroom (or in photoshop) by adding extra blue to the image.
(btw: in the darkroom, 'adding blue' means turning up the yellow in your color pack...I won't get into all that here.)
It is also possible to use tungsten-balanced film to alleviate the problem altogether. However, if that film is used outside under beautiful, natural light, strange things happen.

Florescent lights result in an overall green muddy look on film. Our eyes are used to how things look under flourescent lights; we may not notice how sickly and awful people look under them until they are caught on film. You can compensate for that by adding magenta to the image, again either in the color pack on your enlarger or in a photoshop-esque program.

A little manipulation with color settings can make a world of difference for problems due to artificial light sources. But beware that whenever you resort to dramatically changing the color balance in your program settings or enlarger, you can lose alot of detail, crispness and contrast in the image.

One way to get around dealing with these problems is to use the flash, your camera's very own and very purposeful artificial light source. The flash takes care of the yellow you'll get from tungsten lights; it attempts to create a white light similar to what you might find outside. However the flash causes its own problems if you are bothered by the fact that the direct bright central light on your subject has *flash!* written all over it. It also takes away alot of the beautiful patterns and shadows you might enjoy with overhead or side lighting.

Of course, professional studio photographers needent worry about any of this hoo-hah because they can employ a vast array of standing lights and colored cells to produce any effect they desire. But for photographers who prefer the spontaneity of 'real life' shooting to the calculatedness of the studio, standing lights aren't necessarily practical or available. In this case, if you must shoot in the dark and want to avoid that blatant, head-on flashy look, a remote flash is a god send. This enables you to utilize the good aspects of having a flash around, but not be limited to the direct, head on direction of an on-camera flash.