Region is the term used to designate the different areas in which World of Warcraft service is offered. The current regions are Americas, Europe, China and Korea. World of Warcraft accounts are region-specific, and only allow for use of features related to that region, including access to servers.
Each region features its own selection of servers or 'realms'. For a full realm list by region, see realm list.
Characters cannot be transferred to realms in other regions, and players cannot communicate with or invite players from other regions. Cross-realm features such as cross-realm zones and battleground instances do not function cross-region, and all leader boards and ladders (eg Challenge Mode) are currently region- or realm-specific. The result of these limitations is that players are unable to communicate, interact, transfer or compete cross-region.
Region also determines factors such as support and forum access. The US and EU have separate official sites for the game, featuring separate forums; only players with an active account in the corresponding region are allowed to post on that region's forums. Additionally, certain features are at times made available to US players before those of other regions. Since the vast majority of all developer and 'blue' forum posts are made on the US forums, this has led to dissatisfaction among some EU players, who are unable to join in these discussions due to region restrictions, and claim to feel less heard due to fewer responses from blues.
Different regions are notable for featuring different player trends. For example, while all regions can be accessed from multiple time zones, some feature a higher number of players within a certain time zone, which can lead to strong spikes in server stress at peak times. The EU region has been described as "more compressed" than the US, with a larger proportion of players playing during the same times, leading to greater server stress problems than in the US region. The EU has also been stated to have more servers with very high populations than the US. EU players have been described by Lead Encounter Designer Ion Hazzikostas as "slightly more hard-core raiders than the rest of the world". For some related statistics for US and EU servers, see realm statistics.