動(dong)(dong)(dong)(dong)(dong)車(che)、全稱(cheng)動(dong)(dong)(dong)(dong)(dong)力(li)車(che)輛(liang)，是指軌道(dao)交通(tong)系統中裝(zhuang)(zhuang)有(you)(you)動(dong)(dong)(dong)(dong)(dong)力(li)裝(zhuang)(zhuang)置的車(che)輛(liang)，包括機(ji)車(che)和動(dong)(dong)(dong)(dong)(dong)力(li)車(che)廂兩大(da)類。動(dong)(dong)(dong)(dong)(dong)車(che)裝(zhuang)(zhuang)配有(you)(you)驅動(dong)(dong)(dong)(dong)(dong)車(che)輪，而與之相(xiang)對應地無驅動(dong)(dong)(dong)(dong)(dong)裝(zhuang)(zhuang)置車(che)輛(liang)就(jiu)是拖車(che)。列車(che)要能在軌道(dao)上正常(chang)運行，就(jiu)必須有(you)(you)動(dong)(dong)(dong)(dong)(dong)車(che)為整列火車(che)提(ti)供(gong)足夠牽引力(li)，但(dan)可以不掛沒有(you)(you)動(dong)(dong)(dong)(dong)(dong)力(li)的拖車(che)。