I am implementing a map renderer for Quake. I am currently running through the arrays of vertices and sending them one at a time. I was told that by using vertex arrays, I can greatly speed up the rendering process by sending vertices in a batch. Now, I have just looked at display lists and finally VBO's or vertex buffer objects. VBO's mention a great advantage in relation to client/server communication. IF I am just going to be developing a client and not a server, are VBO's still applicable to what I am doing?
What are games using currently in the OpenGL spectrum for quick vertex processing?
When they say "client/server" communication, they are not talking about a internet network.
These are two separate pieces of hardware. While they are (usually) attached to the same motherboard, they still need to communicate with each other. A graphics card doesn't usually have access to the main memory on your motherboard, so vertices (and textures, indices etc.) need to actually be sent to the graphics device.
Short story: Use Vertex Buffer Objects. For static data (like a Quake map) there is nothing better. The vertices are sent to the graphics device (server) once and stay there. When you draw things vertex by vertex (using something like glBegin(GL_TRIANGLES)) the vertices are sent across every frame, which, as you can imagine, is pretty inefficient.