Here's a slightly different way of looking at singing:

Singing is a precision physical discipline, like for example playing darts or doing gymnastics.

A darts player has to learn precision control of the muscles of his arm. The gymnast has to learn precision control of the arms, legs and muscles. What does a singer have to learn?

To sing well, a singer needs a strong, powerful, flexible voice. What special skills does the singer need to develop in order to achieve this? The following goes some way to answering this:

There are several areas of skills/awareness on which good vocal performance depend. Among which are:

• Lingual ability: simply, the ablity to do stuff with the mouth over & above habitual everyday speech.
• Vowel flexibility: The ability to alter vowels, for example in "putting on" accents. More likely to be found in people who speak more than one language, as to do this you need to understand that vowels are not "fixed" but can vary according to circumstance.
• Posture: The ability to stand and move in a relaxed way.
• Breathing: The ability to voluntarily draw breath into the bottom pat of the lungs
• Intention: The intention to make a strong sound. Note this is different from simply wishing for a strong voice. Strong voice = a feeling of being loud. Many people are not prepared for this. A teacher can show you how to get what you wish for. You need to wish for the right thing!
• Accurate hearing: You need to be able to distinguish timbres within music... for example pick out one instrument in a busy musical mix. Or tell an oboe from a cor-anglais. The ear is the primary organ of singing.
• Basic music knowledge: Many singers are held back because they feel that they don't know enough about singing or music. If you just understand counting and some basic stuff about keys & chords you will feel more "worthy" of taking the lead.