Hanuman Chalisa is a devotional song based on Lord Hanuman as the model devotee, it is written by Mahakavi Goswami Tulsidas in the sixteenth century in praise of Lord Hanuman.

The song is called a Chalisa as it contains forty (Chalisa in Hindi) verses. The structure of the poem is extremely simple and rhythmic, thus making it all the more popular. The word "chālisā" is derived from "chālis" in Hindi, which means 40, as the Hanuman Chalisa has 40 verses.