This book explores the notion of whether we can be friends with machines in a philosophically meaningful way. Depending on our concept of friendship, we may be inclined to answer differently. Since social technology has made new forms of friendships possible between people across the globe, the author argues that the philosophical concept of friendship, forged thousands of years ago, should be re-examined. The author proposes a new approach to the debate that reflects the unique relationship we can build with machines as our synthetic friends.