These are the Warcraft 1: Orcs and Humans units for Humans. The units are listed from starting units onwards.
Peasant
Cost: 400 Gold
Attacks/Magic? No, No
Requirements: Great Hall
Peasants are the builders and workers of the society. They harvest wood and gold, build simple farms, and also build advanced structures like the Stable. However, they are defenseless, making them run when attacked by the orcs.
Footman
Cost: 400 Gold
Attacks/Magic? Yes, No
Requirements: Barracks
Footman are the most basic soldiers that serves the King. They carry a sword and a shield, covered in armor, but move slow.
Archer
Cost: 450 Gold, 50 Lumber
Attacks/Magic? Yes, No
Requirements: Barracks, Lumber Mill
Archers are ranged units, firing their crossbows at the orcs. However, they are weak in armor, making them fast but vulnerable to close combat units.
Cleric
Cost: 700 Gold
Attacks/Magic? Yes, Yes
Requirements: Church
Clerics are the healers/protectors of Azeroth, healing and casting spells to heal and protect the army. They can heal, see farther, and make the user's units invisible, only to be weak because of lack of armor.
Knight
Cost: 850 Gold
Attacks/Magic? Yes, No
Requirements: Barracks, Stable, Blacksmith
Knights are the fast, mounted riders of the King's army. They ride, swift and deadly, placing fear to the orcs.
Catapult
Cost: 900 Gold, 200 Lumber
Attacks/Magic? Yes, No
Requirements: Lumber Mill, Barracks, Blacksmith
Catapults are the machines of the army, hurling fireballs of death at the enemies. They do splash damage, destroying all, human or orc, into annihilation.
Conjurers
Cost: 900 Gold
Attacks/Magic? Yes, Yes
Requirements: Tower
Conjurers are the wizards of the society, casting spells for the King. They can summon creatures to their will, cast fiery storms, and wield deadly spells.