"The Interpretation of Dreams" by Sigmund Freud proposes the importance of dreams as the manifestation of wish fulfillment, telling us the inner desires of a person. In the book Freud also proposes a double meaning of dreams, childhood sexuality and a universal language of dreams.
Freud's most famous work, the book "The Interpretation of Dreams" was published in 1900 and is considered a breakthrough work in psychological theory to this day. In the book, Freud explains that there is a double meaning of dreams: the surface level of "manifest content," which is the things that actually happen in the dream, and the "latent content," the dream's true meaning. This latent content comes from people's repressed longings and allows the person to act out unacceptable desires in the dream life.
Freud believed that the manifest content had symbology that related to sexual desires and the person's true wishes. For example, a dream about a train going through a tunnel is a representation of sex and indicates a person's sexual needs. Interpreting his patients' dreams assisted Freud in his analysis of neurotic behaviors and in diagnosis of his patients. To this day, psychologists study and use Freud's theories to help their patients.