Highlight any object:

By default, the typeset form of Highlighted[expr] evaluates to itself:

This can be changed using the option StripOnInput:

Highlighted[…,None] can be used to remove automatic highlighting from specific elements:

Highlight the first curve with a labeled ball that follows the cursor:

Highlight a fixed location with the labeled ball:

Use the "Dropline" effect to show a point labeled with the coordinates and droplines to the axes:

Place a fixed highlight at and :

Use the "XSlice" effect to show a vertical line and labels::

Place a fixed highlight at :

Use the "YSlice" effect to show a horizontal line and labels:

"IndicatedPoint" shows a point when the position is close to a plot element:

No point is shown if the position is too far from the plot element:

Automatically find a point based on the value:

"NearestPoint" shows the nearest point to the position in the plot element:

The point is shown even if the position is far away from the plot element:

Automatically find a point based on the value:

"XNearestPoint" shows all the points that share the same value as the position:

"YNearestPoint" shows all the points that share the same value as the position:

Use the "Style" property to change the appearance of the points:

"Crosshairs" draws vertical and horizontal lines at the position:

"XYDropline" draws droplines from the position to the axes:

Find the position on the curve closest to :

"XLine" and "YLine" draw vertical and horizontal lines across the plot:

"XDropline" and "YDropline" draw vertical and horizontal droplines to the axes:

If there are multiple points, multiple droplines will be drawn:

Use the "Style" property to change the appearance of the lines:

"XYLabel" labels the plot elements with the coordinates:

If there are multiple points, each is labeled:

"XLabel" shows the coordinate corresponding to the value of the position:

"YLabel" shows the coordinate corresponding to the value of the position:

Label effects take Callout options as styling parameters:

Create a custom effect by combining different components:

Style the different elements in the effect:

Specify a highlight color:

Bottom align a series of highlighted expressions:

Set the base style for the contents to a different font size and color:

Remove extra whitespace around a label with no ascenders or descenders:

Add a frame around the highlighted expression:

Add margins within the highlighted frame:

Change the frame style:

Add margins outside the highlighted region:

Set the highlighted frame to a fixed image size:

Change the rounding radius for the corners:

Create a highlighted output that evaluates to the first argument of Highlighted:

When the output is used as input, the Highlighted wrapper disappears:

When the hold is released, evaluation proceeds normally:

An explicit setting StripOnInput  False will be removed when the output is used as input: