The Marine is often considered the substance of the Terran army and the first line of defence. The Marine is available from the Barracks as soon as the Barracks is built.
In Starcraft 1 Marines produced from the Barracks had considerably smaller range and ten less HP. In StarCraft 2 the Marine has 45 HP and can be upgraded to have 55 HP and it also comes with the range upgrade, which you’d have to purchase in Starcraft.
The Marine can still use the Stimpack ability, which has to be purchased before hand and can be upgraded with the “Combat Shield” which adds an additional 10HP.
