Actually, that is not the only way to play music. It's also possible to scan the music with the eyes, to sight read, and produce a good rendition of the piece. I think sight reading is analygous to reading words. For instance, we can all pick up a book or newspaper and read it right away. There's no repetition or special preparation of any kind needed. Sight reading is very similar to casually reading a book or newspaper you've never seen before.
Characteristics of a Good Sight Reader
A good sight reader keeps solid time. In other words, the tempo remains steady. It doesn't speed up or slow down. This is crucial if you are sightreading for a choir or instrumental combo. The piano is often the time-keeping instrument in the ensemble, or it is one of them. The other musicians, whether singers or instrumentalists, having a difficult time performing their part if the tempo keeps moving around. Think about how hard it would be to follow a person reading a story to you if they kept halting at unpredictable intervals, or they kept speeding up and slowing down.
A good sight reader makes the structure of the music clear. You wouldn't want someone to read a news article to you with no regard for periods or paragraghs. If they just recited a string of words you might not even comprehend the article. When you sight read, you should try not to miss cadences, key changes, mood changes, etc., so that your audience can understand the music.
In addition, you should try to be as relaxed as possible. As I mentioned above, ensembles often look to the pianist for tempo and overall rhythmic foundation. If you are confident, the whole ensemble will benefit (In some ensembles the pianist is a follower as well as a leader, but that's another subject).
Boy this sounds pretty demanding, doesn't it? Well, it takes a little time to get the hang of sight reading, but not as long as you might think. Let's look at some ways to get started.
