The Myth of Sisyphus (1942) by Albert Camus is a series of essays on the absurd. The book referred to here also had some essays on North African cities as well as an interview. It’s a book I read in the last years of high school and one I haven’t read since.
The essay on the absurd is a succinct exposition of Camus’ existential position. Wikipedia has a really good summary of the essays.
The essays on North African towns are interesting in how they describe exactly what Camus thought of the places where he set most of his novels.
There was also an interview with Camus that wasn’t particularly interesting.
For anyone interested in existentialism The Myth of Sisyphus is a great primary source to read. It’s a pleasant read, far more so than Heidegger or Kierkegaard.