Short answers, pulled from the story.
The ranger class was primarily based on Aragorn and the Rangers of the North from J. R. R. Tolkien's Middle-earth. The AD&D second edition handbook also cited Robin Hood, Jack the Giant Killer, the huntress Diana, and the Greek hero Orion as inspirations.
The ranger first appeared in The Strategic Review, volume 1, number 2. It later became one of five subclasses in the Advanced Dungeons & Dragons 1st edition Player's Handbook.
Screen Rant rated the ranger as the least powerful of the 12 base classes in 5th edition because its favored enemy and favored terrain bonuses become ineffective when the dungeon master sets the adventure outside those chosen specialties. The Beast Master subclass in particular has drawn criticism for poor damage output and weak class-specific abilities.
The Revised Ranger was released in 2016 as part of the Unearthed Arcana playtest material in response to criticism of the standard ranger class. It made core abilities easier to use and fixed the Beast Master's animal companion, granting it at level 3 and allowing both the ranger and the animal to act on the same turn. It is not legal for organized play in the Adventurer's League.
Data from D&D Beyond covering the 15th of August to the 15th of September 2017 showed rangers as the 6th most created class, with 8,887 total characters. Elf ranger was the second most popular class and race combination overall, with 3,076 elf rangers recorded.
Xanathar's Guide to Everything (2017) added the Gloom Stalker, Horizon Walker, and Monster Slayer. Tasha's Cauldron of Everything (2020) added the Fey Wanderer and Swarmkeeper, and also introduced optional class feature variants including a revised Beastmaster companion.