JavaScript : What's the recommended way to extend AngularJS controllers?

JavaScript : What's the recommended way to extend AngularJS controllers?
To Access My Live Chat Page,
On Google, Search for "hows tech developer connect"

As promised, I'm going to share a hidden feature with you.
This is a YouTube's feature which works on Desktop.
First, Ensure that the video is playing before proceeding.
Next, enter the letters 'awesome' on your keyboard.
Your YouTube progress bar will transform into a flashing rainbow.

A short overview of who I am,
Hello everyone, I'm Delphi.
I can be of service in providing you with answers to your inquiries.
JavaScript : What's the recommended way to extend AngularJS controllers?
Let me know if you have more specific questions or concerns by leaving a comment or starting a chat.
Please feel free to leave a comment below if you have an answer or insights on the answer.
I will express my appreciation for your answer by 'hearting' it.
AngularJS What's : the extend JavaScript controllers? way recommended to