The average house will be equipped with what are known as compression faucets. These get their name from the fact that a soft rubber or fibre washer inside of them is compressed down when you turn the handle, and blocks off the orifice or hole through which the water passes. Continued use wears the washer away or distorts it so that it does not completely close the orifice, whereupon you have a dripping faucet or one that runs continuously. To change the washer takes about five minutes. The water should be shut off either at the main or at the control valve under the fixture. Unscrew the bonnet or cover of the faucet through which the stem passes, and then keep turning the handle as though you were turning the faucet on. The stem, bonnet, and handle will come right out of the faucet, and you will see the washer on the end of the stem. Remove the small set-screw which holds the washer in place, and replace it with another exactly the same size. Have no fear of replacing things in the wrong way, because the construction of modern faucets is such that it will be impossible.
There is nothing at all complicated about the average standard hot or cold-water faucet. The small washer which closes or opens the orifice through which the water flows, is easily replaced.
You will always find that faucets that are in constant use will give the most trouble. The kitchen sink faucets for instance. You will also find that the hot water faucets need re-washering more often than the cold water, because the hot water burns the life out of the washer more rapidly. You should keep a small box of assorted washers on hand, and you should buy goods ones. Cloth-inserted rubber or good fibre washers will last for quite a few years, while the cheap compressed paper variety may not last for six months. The difference in price between the two is not even worth mention.
You may notice sometimes that the handles of the faucets, which at first were in alignment, gradually have moved out of line. They can always be straightened out and matched up, by simply removing the screw on top of the handle, lifting the handle off the stem and replacing it in line with the other. When the handles are matched up the fixture looks more shipeshape and orderly.