A context is a set of parameters and
wrapper specific options which modify or enhance the
behavior of a stream. Contexts are created using
stream_context_create() and can be passed to most
filesystem related stream creation functions (i.e. fopen(),
file(), file_get_contents(), etc...).
Options can be specified when calling
stream_context_create(), or later using
stream_context_set_option().
A list of wrapper specific options can be found in the
Kontextoptionen und -parameter chapter.
Parameters can be specified for
contexts using the
stream_context_set_params() function.
Two important terms: - An *option* is a protocol-specific setting, e.g. "method" (get, post, put...) if you are using HTTP or "callback function to be called when inserting a document" in MongoDB.- A *parameter* is a settings that's common to all protocols. As of 2015 only one parameter got implemented ("notification").While these words might look vague they are used coherently throughout the stream feature, documentation included.