In the essay writing part, they asked to write about environmental damage by humans. Not only coherence, they also checked the essay presentation during the interview round.
As far as interview is concerned, here goes.
He first asked me to introduce myself. After about a minute of explanation, there were general questions such as:
Since I came from a different field, he asked why I wanted to shift.
What was my career goal or what sort of job I'd like.
Another question was a situational one in that how I will go about choosing a mentor for myself in a group of teams. Complicated the question depending on my answers.
My hobbies.
What I like about the company that got me interested enough to apply.
Checked how much programming I knew.(Just a very basic question which I still failed to answer but I kept trying anyway)
Before leaving I was asked if I have any questions in mind. I asked how his journey in TechM was and if he would recommend it to someone, not as a HR but as an employee. Until the introduction and during the questions-from-my-side phase, I ensured the tone was set to casual if not semi formal; it was formal otherwise.