Public speaking is almost as ancient as speech itself. The first textbook on the subject was written over 2400 years ago, and the principles elaborated within it were drawn from the practices and experience of orators in ancient Greece. These basic principles have undergone modification as societies and cultures have changed, yet remained surprisingly uniform.
Effective public speaking can be developed by joining a club such as Rostrum, or Toastmasters International where members are assigned exercises to improve their speaking skills. Members learn by observation and practice and hone their skills by listening to constructive suggestions followed by new public speaking exercises.
The fear of public speaking is called glossophobia. It is believed to be the single most common phobia, effecting as much as 75% of all people.
See also: Debate, Rhetoric, Toastmasters International