Somewhat related to the Magit selection described in the previous section is the hunk-internal region.
Like the selection, the hunk-internal region is based on the Emacs region but causes that region to not be visualized as it would in other Emacs buffers, and includes the line on which the region ends even if it ends at the very beginning of that line.
Unlike the selection, which is based on a region that must begin in the heading of one section and ends in the section of a sibling section, the hunk-internal region must begin inside the body of a hunk section and end in the body of the same section.
The hunk-internal region is honored by "apply" commands, which can, among other targets, act on a hunk. If the hunk-internal region is active, then such commands act only on the marked part of the hunk instead of on the complete hunk.