How to use Functions on Asterisk Dialplan Context

Asterisk functions are very similar to functions in many programming languages. Functions are: Sophisticated subroutines that help you manipulate data in a variety of ways. Dialplan Functions tend to be geared towards manipulating channel data and attributes as well as providing general tools for manipulating data in variables and expressions, whether they are channel related or not. For more explanation on this video: https://www.linuxhelp.com/how-to-use-functions-on-asterisk-dialplan-context