1) www.youtube.com/watch?v=sUrV6oZ3zsk&feature=youtu.be A good introduction to how we define and measure personality.
2) www.youtube.com/watch?v=sUrV6oZ3zsk&feature=youtu.be This video offers a clear explanation of one of the grand theories of personality: psychodynamic theory.
3) https://www.youtube.com/watch?v=3UcjojHetfE&feature=youtu.be A summary of another grand theory of personality, humanism, as developed by Abraham Maslow and Carl Rogers.
4) www.ted.com/talks/brian_little_who_are_you_really_the_puzzle_of_personality?referrer=playlist-who_are_you
In this TED talk, Brian Little explores the malleability of personality, exploring ways in which people act out of character in certain situations.
5) https://digest.bps.org.uk/2015/04/27/you-can-change-your-personality-at-will/
This review article looks at recent research into the possibility of volitional personality change.