I agree with the advice already given as regards outdoor plants. However, as pointed out by wax eagle, apart from cacti and succulents, most indoor plants, dislike the dry air produced by central heating in winter (unless you have a humidifier, of course, or they live in the bathroom or the kitchen) and they will suffer - many may not survive - unless you give them the humidity they need. You can create a moist microclimate around them by:
misting the whole plant by spraying it with tepid water - but not in bright sunlight, for the reason given by winwaed, or
placing the pot or, better still, a group of pots, on a layer of pebbles at the bottom of a shallow tray, into which you have poured a little water, just enough to almost cover the pebbles but not to enter the bottom of the pot, or
double-potting - putting one pot inside a larger pot or container, and filling the gap between them with moss which will need to be kept continually damp.
If the leaf tips of your indoor plants turn brown and shrivel, or the leaves wilt, although the plants are being watered sufficiently, this is usually a sign that the plants need more humidity in the air.