Sample space of n consecutive coin flips
Jelly, 4 bytes
⁾HTṗ

A monadic Link accepting a non-negative integer which yields a list of characters.
Try it online! (footer calls the Link and joins with newline characters)
How?
⁾HTṗ - Link: integer, n
⁾HT  - list o characters = ['H', 'T']
   ṗ - (that) Cartesian power (n)