The words hall, haul sound the same but have different meanings and spellings. Why do hall, haul sound the same even though they are completely different words?
The answer is simple: hall, haul are homophones of the English language.
A corridor or passageway in a building.
A large entrance room or vestibule in a building; a lobby.
A building for public gatherings or entertainments.
The large room in which such events are held.
To pull or drag forcibly; tug. See Synonyms at pull.
To transport, as with a truck or cart.
Informal To compel to go, especially for trial: "hauled the huge companies into court” ( Peter Matthiessen).
Nautical To change the course of (a ship), especially in order to sail closer into the wind.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.
If they are spelled the same then they are also homographs (and homonyms); if they are spelled differently then they are also heterographs (literally "different writing").