From Minecraft Parkour Wiki
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Parkour is the art of displacement, a discipline which consists in getting from a point to another through agile movement.
In Minecraft, this translates to crossing arbitrary obstacles, sometimes using complex techniques and mechanics.

This goal of the MCPK wiki is to document the knowledge accumulated by the parkour community over the years, which has been largely acquired through observation and deduction. This "top-down" approach has led the community to discover mechanics such as 45° Strafe and Blips, but never to properly explain how or why they work.

Hence, a secondary goal of the MCPK wiki is to reverse-engineer the code related to movement, and work upwards from there. This "bottom-up" approach is more arduous, but has given precious insights into previously known mechanics, and also led to the discovery of complex glitches that couldn't have been discovered through observations alone, such as Half Angles.