Several options specific to sketches and planes appear in the context menu when right clicking on them in the feature Tree Outline.
Context Menu Options
Always Show Sketch: Makes the selected sketch
always visible, even when viewing another plane. Applies only to sketches.
Show Sketch: Returns the sketch
to its normal viewing mode. The sketch will be visible if the plane
it belongs to is visible. This is the default visibility setting.
Applies only to sketches.
Hide Sketch: This allows you to turn off the
display of a sketch. While hidden, it will only be displayed when
it is selected in the feature Tree Outline, or
is the active sketch while in sketching mode. While hidden, its edges
will not be used for auto constraints or dimensions, unless it is
the active sketch. Applies only to sketches.
Look At: Orients the display so that it is
centered on the selected sketch or plane.