Interviews are a free way to test your skills - getting yourself tested for concepts by experts and in turn becomes rewarding too if you are really adept at the skills in question.

If there's a knowledge gap that is discovered, you would know about it and this is an opportunity to learn, fix the gaps, improve and in turn grow as a professional.

What you must not do during the interview:

• Never argue with your interviewer. You would most likely get rejected.
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About asking the questions to the interviewer during the end of an interview, some of my favourite questions are:

• How's the culture of the organisation? Work Life Balance?
• Do you enjoy your work? 
• What would be the Career progression opportunities in the firm/ What will be my Career path in the firm?

WIP