What is self-realization? Who am I?

Why is it so hard to answer this question without using the titles we have acquired through life? Who am I under my clothes, behind personas I put on, devoid of titles I gathered from external institutions?
The yoga tradition has invested thousands of years in carving out a path of self-realization. I will explain why this idea of self-realization can be so eluding and why it is essential. I will employ terminologies from Western Philosophies to make the topic more tangible.