An engine lathe can be a gap bed lathe. The term "gap bed" refers to a lathe where a section of the bed next to the head stock is removable to enable the machining of large outside diameter work...
A turret lathe has six-usual tools arranged in the order of use on a rotating turret which is cycled by a large wheel or (Turnstile) like contrivance- in fact some lathe makers calle them Turnstile...
They are essentially the same machine. Capstan is British usage, Turret, US. One old and still technically correct usage of Capstan was the (Turnstile winch) were Bars were extended and seamen walked...
The difference between milling and lathe machining is that on a milling machine the cutter is static and rotates and the workpiece is moved around to enable the machining to it. On a lathe, the...