There are three versions

• The classic Ranger as given in the PHB.

• The Ranger with No Spells as given in the Unearthed Arcana: Modifying Classes.

  • This version removes the spellcasting progression from the class and gives them a more nature-based theme. This version has included in it Superiority Dice (from the Fighter's Battle Master archetype) and various abilities that mimic spells, but are explicitly nonmagical.

• The Revised Ranger, which is also in the Unearthed Arcana.

  • This version of the class is what a lot of people enjoy. It upgrades the strength of many of the classic Ranger's abilities. Its Favored Enemy and Natural Explorer abilities are so good, it becomes worth it to consider a 1-level dip in this class just for those abilities.

These three versions of the Ranger are, in essence, different classes which all just happen to share a name. There are, of course, many archetypes/conclaves, but those minor differences do not constitute a totally different release/version of the Ranger.

There are three (and a half) versions

• The classic Ranger as given in the PHB.

• The Ranger with No Spells as given in the Unearthed Arcana: Modifying Classes.

  • This version removes the spellcasting progression from the class and gives them a more nature-based theme. This version has included in it Superiority Dice (from the Fighter's Battle Master archetype) and various abilities that mimic spells, but are explicitly nonmagical.

• The Revised Ranger, which is also in the Unearthed Arcana.

  • This version of the class is what a lot of people enjoy. It upgrades the strength of many of the classic Ranger's abilities. Its Favored Enemy and Natural Explorer abilities are so good, it becomes worth it to consider a 1-level dip in this class just for those abilities.

• In the 2019 Class Feature Variants UA the Ranger (in pdf) was given several alternate, or appending features.

  • The core class is still the one in the PHB, but was given optional features to replace certain features (Natural Explorer, Favored Enemy, etc.), append to options (including a Fighting Style which grants druid cantrips), or add to the spellcasting feature (including adding spells to the class list, spellcasting focus, and the ability to replace spells on long rests).

These three (and half) versions of the Ranger are, in essence, different classes which all just happen to share a name. There are, of course, many archetypes/conclaves, but those minor differences do not constitute a totally different release/version of the Ranger.

There are three versions

• The classic Ranger as given in the PHB

• The Ranger with No Spells as given in the Unearthed Arcana: Modifying Classes

• The Revised Ranger, which is also in the Unearthed Arcana

These three versions of the Ranger are, in essence, different classes which all just happen to share a name.

Though there are only three versions, there are many more archetypes/conclaves to further distinguish Rangers from each other. There are two classic ones for the classic Ranger, and three conclaves for the revised version. The Unearthed Arcana has a large list of new archetypes/conclaves that work for either the classic or revised versions of this class.

And of course, there's an infinite number of variations from Ranger to Ranger, like feats, hitpoints, armor, items, etc. For the purposes of this question, these granular details are not considered as large enough to cause us to consider the character is now a different "version" of Ranger.

There are three versions

• The classic Ranger as given in the PHB.

• The Ranger with No Spells as given in the Unearthed Arcana: Modifying Classes.

  • This version removes the spellcasting progression from the class and gives them a more nature-based theme. This version has included in it Superiority Dice (from the Fighter's Battle Master archetype) and various abilities that mimic spells, but are explicitly nonmagical.

• The Revised Ranger, which is also in the Unearthed Arcana.

  • This version of the class is what a lot of people enjoy. It upgrades the strength of many of the classic Ranger's abilities. Its Favored Enemy and Natural Explorer abilities are so good, it becomes worth it to consider a 1-level dip in this class just for those abilities.

These three versions of the Ranger are, in essence, different classes which all just happen to share a name. There are, of course, many archetypes/conclaves, but those minor differences do not constitute a totally different release/version of the Ranger.