An apparatus for pumping or compressing a fluid, the apparatus comprising: a housing having a front wall, a rear wall and one or more side walls interconnecting the front and rear walls to define a fluid rotation chamber; at least one inlet located substantially centrally in the front wall; an impeller located at least partially within the at least one inlet such that at least a portion of the impeller extends outwardly beyond at least a portion of the front wall; and at least one outlet, wherein rotation of the impeller causes fluid entering the apparatus through the at least one inlet to rotate within the fluid rotation chamber prior to exiting the apparatus through the at least one outlet.