The Stranger is a very short philosophical novel which explores the absurdity of human existence. This absurdity involves the conflict between the human desire for meaning and purpose, and the universe's unwillingness to clearly provide it to us. The book is written from a very direct first person perspective, not a word is wasted. What can come off as an unusual writing style is really just the unique characterization of the protagonist. Every sentence shows his indifference and detachment from reality and its these traits that end up having an insightful interaction with the absurd and with society itself, and are also pretty hilarious at times. His interactions with other characters are very insightful psychologically, Camus' writing style is very impressive at believably communicating the protagonist's mental state with precision instead of vague prose.
The writing style results in the book being very easy to read at a surface level so I would recommend it to most people. I particularly enjoyed the interesting philosophical commentary and the psychoanalysis of the protagonist. There is more symbolism and philosophical depth to it beyond that surface level if you are willing to dig that deep, but its philosophical conclusions leave much to be desired, even if thats kinda the point.
SPOILERS BELOW
The protagonist is a sort of hero who befriends absurdity through his extremely weird mental state. His mindset of indifference and detachment from reality uncovers an escape route from the absurdity by embracing it and becoming even more indifferent and comfortable with the universe's own indifference.The solution to the absurd is to embrace it, according to Camus.
Through his unique understanding of the absurd he becomes alienated from society, a stranger, as the title suggests. Society punishes him for his unwillingness to participate in their collective ritualistic denial of absurdity by declaring him a psychopath and sentencing him to death based on his unemotional and antisocial behavior at his mother's funeral. This punishment pushes him deeper into nihilism, where he develops further insights into the absurd. In this sequence, Camus effectively accuses society of being an irrational construct to hide the unavoidable truth of absurdity.
His nihilistic attitude forces him to cope with absurdity by embracing it. He forces himself to reject all other ways of dealing with absurdity, particularly religion and family. His toxic and antisocial mindset constructs the world's biggest cope in embracing the absurdity that troubles him, instead of viewing it as an enemy to be overcome. A very disappointing and relatively useless position, but it is certainly a valuable insight into the unaccomplished and toxic mindset which would adopt it.