Snaplr

Snaplr 

Snaplr is a lightweight desktop screen capturing app, 

use it to grab region of your screen then quickly annotate 

it with a easy palette tool set. 

Free to download for Windows and Mac.

Very easy to sue!!

Give it a try below

Screencastomatic

Screencastomatic

Screencastomatic is an amazing programme to use if you want to quickly
show someone how to do something on the computer.
It easily creates a video of what you are doing and saying.
These are called screencasts.