Obama's book "Becoming" told the story of her Chicago roots as well as her time in the White House. The memoir sold over 1.4 million copies in its first week.
A quote: "Being your first lady has been the greatest honor of my life and I hope I've made you proud."
She appeared on the cover of Vogue for the third time and once again won praise for her timeless sense of style.
Obama co-founded the Joining Forces program to expand educational and employment options for veterans.
Obama became the first African-American first lady — and only the third with a postgraduate degree.