In reality, transposition isn’t all that hard to grasp. Put simply, a transposing instrument is one whose musical notes are written at a pitch different from actual concert pitch.
Seventh century music scholar Isidore of Seville said it was impossible to notate music. Boy, was he ever wrong: there is evidence that notation was practiced by the Egyptians in 3,000 BC. Ancient Greece also had a system, and other forms arose in China and Japan. Now you too can know the proper history of the staff.