Isometric view or drawing is a way of presenting design or drawing in three dimensional. In order for a design to appear in 3D, the sides are rotated at a 30 degrees angle. It allows the designers to draw in 3D quickly and with a reasonable degree of accuracy. Isometric length can be said to be a factor of the actual length by 0.816, or we can simply say that proportion of isometric length to actual length is equal to 0.816. The isometric drawings consist of three axes, which include of one vertical axis and two horizontal axis that are to be at 30 degrees angle from their actual point. The major axes of the isometric co-ordinate system have fixed angles in the drawing where the y-axis remains vertical, as in Cartesian coordinate system. However, x -axis and z-axis are tilted by 30 degree and -30 degree, respectively, relevant to the horizontal. Therefore, the angle between the major axes in an isometric representation is 120 degrees. Three axes form the basis for all isometric drawings. Note that isometric axis can be placed in any desired position but the angle between the projections should be of 120 degrees. Any line which is parallel to the isometric axis is termed as isometric.

The three lines OA, OB, OC meeting at a point O and making 120 degree angle with each other are termed isometric axes. The lines parallel to the isometric axes are called isometric lines or isoline. A line parallel to the x-axis may be called an x-isoline.