Solids enclose volume. The following solids are frequently seen and used.
The cross section of a solid is a "slice" of a solid through a given direction.

A prism is a solid with the same cross section for all of its length.
Solids
Cuboid or Rectangular prism

Cube

Triangular prism


Triangular pyramid


Nets
A net is a pattern in two dimensions which, when cut out and folded, will make a solid figure.
Cuboid

Net of a cuboid

Pyramid

Views of Solids Solids can be viewed from top, front, back and sides. e.g. .
View from top .....View from front ..... View from back ......View from side 
Isometric drawings
Isometric graph paper, which is made up of triangles, instead of the usual squares, can be used to draw views of three dimensional objects.
e.g. An isometric drawing of the cuboid is shown below.