Both tram and trolleybus are types of passenger transport powered by electricity. However, they have different capabilities and specifications.
Definition
Tram - public transport operating with rails and electric traction.

Trolleybus is an electrically powered vehicle that combines the capabilities of a bus and a tram.

Comparison
So, a tram has a lot in common with a train. This also applies to the overall appearance, and the metal wheels, and the way of movement - on rails. A trolleybus is akin to a bus: the same body shape, the same rubber tires, the same roadbed used to move.
The difference between a tram and a trolleybus is also manifested in the movement itself. The fact that the tram's track runs on rails deprives such transport of the ability to maneuver, and the curves along which it passes have a larger radius. On the other hand, driving a tram is relatively easy.
It is quite possible for a trolleybus to go around obstacles on the way, for example, cars in front. The radius of the trolleybus lines may be less than that of a tram car. In addition, the tires on the wheels of this vehicle provide better grip on the road surface, which allows you to more successfully overcome the slope upward.
The pantographs located on the roof of both types of transport are also distinguished by their shape: they are diamond-shaped on the tram, and straight on the trolleybus. The trolleybus uses two wires with different poles for movement. In a tram, the role of the second wire is played by rails. The grounding, which is provided in this case, makes the tram more electrically safe means of transportation.
Consider the difference between a tram and a trolleybus when comparing their capacity. In this regard, the tram has the best capabilities, especially considering that, if necessary, the number of its cars can be increased. The hourly load of a “classic” tram line is twice as high as that of a trolleybus.
Table
Tram | Trolleybus |
Looks like a train | Looks like a bus |
Metal wheels | Rubber tires |
Moves on rails | Moves on roadways |
Cannot maneuver | Able to avoid obstacles |
Larger track radius | Can move along lines of smaller radius |
Diamond-shaped pantographs | Straight pantographs |
The role of the second wires play rails | Uses two wires for movement |
More capacity | Less capacity |