Internal VS external Ultrasounds

Crystal • Ectopic 2015 >5 rounds IVF>one beautiful baby boy>one on the way

Does anyone know the imaging difference between an internal vs external ultrasound.

During my 8 week scan it was transvaginal and baby was facing us and on the left hand side. This weeks was an external and baby was on the other side with its back towards us.

So is one a mirror image while the other is a picture image? Meaning it reflects on the opposite side?