Engines have different layouts of cylinder placement. The common ones are
as follows.
Inline
Cylinders placed in a straight line, hence the name.
Vtype
Two banks of cylinders opposing each other at an incline, 45, 60, 90deg.
Flat/Bpxer/
Two horizontally opposite banks of cylinders such as the volkswagen beetle and the Porsches.
Different layouts have different characteristics like the Inlines are smoother but usually leave the car with a higher Hoodline,V and Boxer arrangments are space saving. Manufacturers like Porsche prefer the bpxer because it ideally suits their RR vehicle layout.