The Recode options allow you to recode all or part of a line feature. The Recode All option allows you to recode all the points of a line feature.
The Recode Between option allows you to recode the all the segments between two points on a line feature. After you have entered the new code, each point that starts a segment will have a segment code dimension, M=, added to it which changes the display for that segment.
The Recode Segment option allows you to recode a single segment of a line feature, also using the segment code dimension.