Triangle strips form a strip of connected triangles. To maintain a consistent winding, the vertices are not traversed in the order specified; rather the pattern is

• v0, v1, v2
• v2, v1, v3
• v2, v3, v4
• (and so on)

The advantage of GL_TRIANGLE_STRIP compared to GL_TRIANGLES:

• After the first triangle, specifying the next triangle only requires one additional vertex.  This results in less data to store and process. 
• If there are N triangles, GL_TRIANGLES requires 3N vertices, whereas a triangle strip of N triangles requires only N+2 vertices.

On the GPU, a set of vertices are stored in a buffer. When one calls glDrawArrays with GL_TRIANGLE_STRIP, three vertices are rendered as a triangle.

glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);

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