This is the 3300th most frequent Polish word.
transport
The movement of people, goods, or materials from one place to another.
'Transportu' (the genitive case of 'transport') pertains to specific usage within public systems of transportation.
Czy korzystasz z transportu publicznego?
Do you use public transport?
Here 'transport' is used as a general reference to the act or means of commuting.
Transport do pracy zajmuje mi godzinę dziennie.
The commute to work takes me an hour daily.
In this sentence, 'transportem' (the instrumental case of 'transport') indicates a focus on the business or service of transportation.