RegionPlot3D

RegionPlot3D[pred, {x, xmin, xmax}, {y, ymin, ymax}, {z, zmin, zmax}] makes a 3D plot showing the region where pred is True.

Examples

Plot a sphere:

RegionPlot3D[x^2 + y^2 + z^2 < 1, {x, -1, 1}, {y, -1, 1}, {z, -1, 1}]

Intersection of regions:

RegionPlot3D[x^2 + y^2 < 1 && z > 0, {x, -1, 1}, {y, -1, 1}, {z, -1, 1}]

Please visit the official Wolfram Language Reference for more details.