The way a Capacitor is constructed can greatly affect it’s Capacitance.
Simple Capacitor
Recall how a capacitor is can be modelled as Infinite Parallel Planes Of Charge. In reality, a dielectric material (such as plastic) is sandwiched between two conducting plates (usually made of aluminium), and then rolled into a cylindrical shape:
This way, surface area of the plates is maximised, while distance between plates is minimised.
Electrolytic Capacitors
In an electrolytic capacitor, the dielectric material is a oxide layer, which is extremely thin. Furthermore, the conducting layers are usually etched to maximise surface area.