(given permission to be ignored) by producers, game designers, or even lead testers, according to company policy. Methodology There is no standard method for game testing, and most methodologies are developed by individual video game developers and publishers. Methodologies are continuously refined and may differ for different types of games (for example, the methodology for testing an MMORPG will be different from testing a casual game). Many methods, such as unit testing, are borrowed directly from general software testing techniques. Outlined below are the most important methodologies, specific to video games. Functionality testing is most commonly associated with the phrase "game testing", as it entails playing the game in some form. Functionality testing does not require extensive technical knowledge. Functionality testers look for general problems within the game itself or its user interface, such as stability issues, game mechanic issues, and game asset integrity. Compliance testing is the reason for the existence of game testing labs. First-party licensors for console platforms have strict technical requirements titles licensed for their platforms. For example, Sony publishes a Technical Requirements Checklist (TRC), Microsoft publishes Xbox Requirements (XR), and Nintendo publishes a set of "guidelines" (Lotcheck). Some of these requirements are highly technical and fall outside the scope of game testing. Other parts, most notably the formatting of standard error messages, handling of memory card data, and handling of legally trademarked and copyrighted material, are the responsibility of the game testers. Even a single violation in submission for license approval may have the game rejected, possibly incurring additional costs in further testing and resubmission. In addition, the delay may cause the title to miss an important launch window, potentially costing the publisher even larger sums of money. The requirements are proprietary documents released to developers and publishers under confidentiality agreements. They are not available for the general public to review, although familiarity with these standards is considered a valuable skill to have as a tester. Compliance may also refer to regulatory bodies such as the ESRB and PEGI, if the game targets a particular content rating. Testers must report objectionable content that may be inappropriate for the desired rating. Similar to licensing, games that do not receive the desired rating must be re-edited, retested, and resubmitted at additional cost. Compatibility testing is normally required for PC titles, nearing the end of development as much of the compatibility depends on the final build of the