Eastern RPG

The term "JRPG" can be used in two different ways:

A Role-Playing Game developed in Japan. This usage is becoming increasingly more common nowadays, due to the increasing diversification of Eastern titles.

Or a "Light RPG", a specific subset of Japanese titles that were popular in the 1990s and early 2000s, following certain styles which were popularized by Japanese console developers in the '90s, sometimes differentiated from Western RPGs by having several or more of the following features:

Created in Japan.
Generally found on consoles (and more recently, handhelds) rather than a PC, though in the past many Japanese RPGs were also released for Japanese PC platforms before the country's PC game industry declined in the mid-90s.
Aimed to satisfy the player's need for a well-crafted interactive story with interesting characters and complex interactions.
The art styles can often resemble those of Anime or Manga.
Many can tend to follow linear plots, with less of a Wide Open Sandbox setting, and many may not feature discrete "quests". However, there are many Japanese RPGs that do offer non-linear narratives.
The player usually controls a party of pre-designed characters. The player is sometimes offered a choice of what characters to use, but not the option of designing his own protagonists, which allows a more cinematic and tightly scripted story. But again, there are many Eastern RPGs that deviate from this.

The party members are usually written into the plot, rather than blank slates.
Later games tend to have one or more elaborate, minigame-like "systems" (such as the License Grid in Final Fantasy XII) that allow skill and ability customization.
Random Encounters are a common gameplay element, especially in older games.
Turn-Based Combat and the various Combatant Cooldown Systems are prevalent, although action-based combat has also been popular at different times.
A degree of Level Grinding is strongly encouraged, if not outright required, to proceed through many of the games.
Most encounters are resolved through combat or cutscenes. Most quests and abilities are combat-oriented.
Dice rolls are always hidden and stats are given as arbitrary numbers. Sometimes dice rolls aren't used at all, and fights are based on your stats versus the enemy's stats alone.

The style that was arguably the most popular from the Super Nintendo Entertainment System to PlayStation 2 eras is the turn-based RPG, also known as "Light RPG", which has been building on the classic Dragon Quest and Final Fantasy formulae for a long time. With later generations, the gameplay has been mixing up with other genres (including Action Games, Adventure Games, Simulation Games, and Strategy Games) though the general "explore / get into battles / some variation on turn-based combat" is still going strong for many games within this sub-genre. Ironically enough, despite being characterised by their Asian heritage, this Eastern RPG style has partial roots in the West. Dragon Quest, which in many ways was the Trope Codifier, if not Trope Maker, was directly inspired by Ultima and Wizardry, some of the earliest Western RPG series. Another major influence on this style were Visual Novels, Japanese Adventure Games that emphasized storytelling (though ironically, most Visual Novels revolve around non-linear narratives rather than linear ones).

Another popular subset of JRPG is the Action RPG, which mixes this type of gameplay with the Action Adventure ELEMENTS, so that while it keeps the strongly plotted story, occasionally manga/anime-influenced characters, experience and statistics, the turn-based battle system is done away with in favor of a more real-time method of attack resembling Action Games. The Action RPG sub-genre has its origins in early 80s Japanese RPGs like Dragon Slayer and Hydlide, which combined traditional RPG elements with Japanese Arcade Game action elements. Up until the early 2000s, the majority of action RPGs were from Japan, but in recent years, it is arguably more common to see action RPGs from the West.

Also, many Turn-Based Strategy games are done in "Console RPG style" and are often referred to as "Strategy RPGs" or "Tactical RPGs", though more recent examples of the sub-genre have also incorporated Real-Time Strategy elements. In contrast to the traditional turn-based format above (represented by Dragon Quest and Final Fantasy), tactical RPGs allow more freedom of movement in battle, while the narratives are also more likely to be non-linear, with strategic decisions often having an impact on the way the story unfolds. This tactical RPG style has traditionally been dominated by Japan, since Western turn-based RPG's usually already allow for freedom of movement in battle by default.

Another subset is the Dungeon Crawler, a subgenre that can include both Eastern and Western games. This subgenre was more common among Western RPGs up until the 1990s, but has today become more popular in the East than it is in the West.

In the past, the Japanese Console format was arguably more prolific and hence more popular than the Western Computer format, with even some Computer games mimicking Console ones. Lately, however, the Computer format is becoming more popular in the West, rivaling (and sometimes even trumping) the Console format in popularity, partly due to progresses in technology making arguably more immersive games, which in turn has led to rising budgets. At the same time, the Japanese market has largely shifted away from consoles, towards handhelds. Many Console development teams nowadays focus more on handhelds due to lower budgets. The most successful handheld RPG franchise is Nintendo's Pokémon, which went on to become the highest-grossing entertainment media franchise of all time. On the console side, there are still larger Japaense development teams that continue to develop for consoles, including Square Enix, Monolith Soft, Atlus, and FromSoftware, with an increasing focus on Wide Open Sandbox Action RPG gameplay.