These reference options specified to the package at loading time. For optional arguments to macros or environments, use {optional-arguments} instead.
These reference options specified to the package at loading time. They are intended to modify the default loading parameters for the package.
Typical usage would be via
\usepackage[<options>]{<package>}
Other methods may be specific to the package. For example, hyperref supplies the macro \hypersetup{<options>} to specify package options after loading the package itself. geometry does something similar through \geometry{<options>}.
Options may also be passed to a package; typically used when writing a package that relies on other packages. The macro \PassOptionsToPackage is used for this.
The LaTeX kernel provides \DeclareOption, \ExecuteOption and \ProcessOption macros, whereas the xkeyval package extends the possibilities for package and class options.
