An Access Key allows a computer user to immediately jump to a specific part of a web page via the keyboard. In Wikipedia, Access Keys allow you to do a lot more - protect a page, show page history, save your changes, show preview text, and so on. See the next section for the full list.
Most web browsers require holding down one or two "modifier" keys to use an access key. Different web browsers invoke access keys in different ways. Please use the list below to determine the appropriate key combination for your browser and system:
The accessibility of keyboard shortcuts (access keys) is a complicated matter. This feature, in its current implementation, was temporarily abandoned in WCAG 2.0, notably because it conflicts with the shortcuts of assistive technologies. Usage of access keys is currently discouraged in the online contents and applications.
But presence of access keys is also an Authoring Tool Accessibility Guidelines (ATAG) requirement—the ATAG approach is particularly relevant in Wikipedia's case—where this matter is looked into thoroughly. In particular, ATAG requires the possibility to customize shortcuts. This should be requested in bugzilla:477.
Currently, their presence in Wikipedia's interface can be problematic for some users and can be useful for others. But more importantly, it misleads developers into thinking that the interface is keyboard accessible. Requirements that need to be fulfilled for a website to be keyboard accessible are not related to keyboard shortcuts (G90, F42, SCR35, F58, F61).