"Alexander and the Terrible, Horrible, No Good, Very Bad Day" is a children's book written by Judith Viorst. It tells the story of a young boy named Alexander who experiences a day filled with misfortunes. From waking up with gum in his hair to facing challenges at school and home, Alexander feels that everything is going wrong. Throughout the story, Alexander expresses his desire to move to Australia as a way to escape his troubles. The book highlights themes of frustration and resilience, showing how even the worst days can happen to anyone, and that it's okay to feel upset about them.