THE PARIS Metro is safe, easy to use and sensibly organized. Mastering it takes about five minutes. Trips are interesting, inexpensive and fast. The first time you reach your destination on the Metro you may feel as good as you did when you first changed a tire.

Fourteen lines serve Paris, each named for its direction (direction refers to the last stop on the line). If a line runs from stop Balard to stop Creteil, for example, the direction of the line is Creteil. On the return, the direction is Balard. To ride the Metro, you need to know the direction of the line and the stop nearest your destination.

You usually have to change lines once and sometimes twice. (The French call changing lines correspondance.) This is not hard. Simply get off at the station where the lines intersect and follow the arrows to the line to which you are transferring.

Many stops have a map with different colored lights for each line. Press a button for the stop you want and lights will come on between your location and your destination. The lights indicate the intersections and the stops along the way.

Riding the Metro is much less expensive than taking taxis. Instead of buying one second-class ticket for 3 1/2 francs, you may buy 10 tickets for 20 francs. Just insert a ticket at the front of the turnstile, go through and pull it out at the back. (There is no need to ride first class.) Car doors do not open automatically; doors open from inside and outside by pulling a handle or pressing a button.

Each stop is different. Some have mammoth elevators; others have stairs, moving floors or escalators. The Metro stop Varenne near the Rodin museum has reproductions of Rodin statues; the Louvre stop near the museum has reproductions of statues on display there. The larger stops often are showcases for musicians, and it is not uncommon to hear Bach well played, or good jazz, as you change lines.