To change the style of a line (linear by default), navigate to the Marks menu, and select one of the options from the Line Style menu:

The linear line shape, the default setting, is a normal jagged line comprised of piecewise line segments that connect the data points.

The basis line shape implements curve-fitting using a B-spline interpolation formulas (generalization of the Bézier curve), with control point duplication on the ends.

Contrast this rendering with the one in Bundle Line Shape.

The bundle line shape implements curve-fitting using a B-spline interpolation formulas (generalization of the Bézier curve), with the tension parameter to straighten the spline.

Contrast this rendering with the one in Basis Line Shape.

The cardinal line shape implements curve-fitting using a Cardinal spline (or canonical spline) interpolation formulas that incorporate a tension parameter, with control point duplication on the ends.

Contrast this rendering with the one in Basis Line Shape.

The monotone line shape is a cubic interpolation that preserves the monotonicity on the vertical axis as it calculates the curve fit.

The step line shape, just as the name implies, alternates between horizontal and vertical segments, starting with a horizontal segment.

Contrast this rendering with the one in Step Before Line Shape.

The step before line shape, just as the name implies, alternates between vertical and horizontal segments, starting with a vertical segment.

Contrast this rendering with the one in Step Line Shape.