<\body> In order to start writing a laptop presentation, you should first select the style using . Currently, there are two main ``themes'' for presentations: the default theme and the theme, which can be selected using . The presentation style includes the style package, which features the use of colors for mathematical formulas, enunciations, etc. Optionally, one may also select the package, which puts frames around section titles and several standard environments. <\initial> <\collection>