What is Critical Thinking?

What is Critical Thinking?
Many times i have been asked to explain what is Critical Thinking as not many seem to be very familiar with this phrase, despite it being used extensively by Business and in Education. There are already many definitions of Critical Thinking out there - but I don't think they help us understand what are the elements of Critical Thinking, or what we are expected to know and practice if we are Critical Thinkers.

Here's a brief presentation about Critical Thinking.

http://www.slideshare.net/prasadarya/what-is-critical-thinking-45871941