Rangers are a late game upgrade of the Scouts, preserving all their Promotions. But with the change in their weapons comes a significant upgrade of their fighting capabilities: not only do they gain a significant Combat Strength boost, they also can now make ranged attacks against enemies up to one tile away. This makes them even better suited for reconnaissance missions, because they can now hold their own for a bit even against late-game units. However, avoid using them for real battle!
Civilopedia entry Edit
“Ranger” has a lot of meanings: a person who roves or ranges; one of a body of armed guards who patrol a region; a soldier trained in commando tactics to make surprise attacks. These days, the common perception of a ranger encompasses all of this. The military use of rangers traces back to the frontier wars between North American colonists and the indigenous natives, who were adept at “irregular” warfare in the trackless forests and swamps. Colonel Benjamin Church, commissioned by the Governor of Plymouth Colony to harry the savages during King Philip's War in 1676, raised a body that was to use the enemy’s own tactics. By the time of the American Revolution, there were several Ranger companies in action against the British, who complained mightily about the methods these colonials used – ambushes, raids, demolitions, sniping, and the like. According to the 'U.S. Army Ranger Handbook,' not much has changed since.