Sliding Sketch allows users to quickly skim through 2D geometry in CATIA V5. In most cases this is sufficient, however, Sliding Sketch does not provide control to two very important Sketch features, source
The lack of a Sliding Sketch is that it is not possible to change the origin and orientation subsequently, and often the subsequent change of the Sketchplane can not be done meaningfully (except in case the new plane is parallel with the current Sketch plane).
The following example shows the difference between Sliding and Positioned Sketch.
The Red Sketch was made as Sliding while Green was created as Positioned. Now we will create two Pocket, from each Sketch one by one, and we have the status as in the picture below.
Now we will change the Sketch Support for Sliding Sketch, and for the plane select the side of the model. As seen in the picture below, Sketch's geometry is outside the 3D model and cannot be positioned in a simple (fast) way.
Clicking on OK appears an exclamation mark in the tree of the model since Pocket does not pass through the originally created Pad.
Now we will change the Sketch Support for the Positioned Sketch, and for the plane select the side of the model. Here we have control over the origin and orientation of Sketch. For the source or orientation, we have a number of options for selecting the existing geometry. It is also possible to rotate the H or V axis of the Sketch or replace them with one another.
After clicking OK, we notice that we have successfully changed the plane of Sketch and thus the position of Pocket