Asterisk Dialplan Syntax - 1

The Asterisk dialplan's configuration file name is extensions.conf which resides in /etc/asterisk/ directory.
The dialplan is made up of 4 main concepts: context, extensions, priorities, and applications.
1. Contexts: Contexts are named groups of extensions. Contexts keep different parts of the dialplan from interacting with one another.
Two sepcial contexts: [general] and [globals]
2. Extensions: Extensions are series of steps that Asterisk will take that call through.
Syntax: "exten => name, priority, application()"
Example: "exten => 212,1,Answer()
3. Priorities: Must be sequence from 1
exten => 212,1, Answer()
exten => 212,n, Hangup()
4. Applications: Each application performs a specific action on the current channel. such as Answer(), Hangup().