OpenGL ES versus OpenGL

Two of the more significant differences between OpenGL ES and OpenGL are the removal of the glBegin ... glEnd calling semantics for primitive rendering (in favor of vertex arrays) and the introduction of fixed-point data types for vertex coordinates and attributes to better support the computational abilities of embedded processors, which often lack an FPU

Have a look here: OpenGL_ES

OpenGL ES is the opengl api for embedded systems. It is simpler than the normal opengl in terms of the number of the api functions, but may be harder to use, since you will have to use vertex buffers and write more shaders.

When you use a normal opengl, you can use glBegin and glEnd to enclose the geometry primitives you need to draw, but when using Opengl ES, you will have to use vertex buffers. I guess this is for performance concerns.

Currently, there are two Opengl ES versions, the 1.1 version can only support the fixed rendering pipeline, while the 2.0 version supports glsl shader. However it has no fixed rendering pipeline. In other word, you will have to write your own shader for everything.

Opengl ES is mainly used on cell phones and web (webgl). According to the spec, your desktop opengl driver can support all opengl es apis.