OpenGL ES 3.0 Introduction

OpenGL ES = Open Graphic Library for Embedded Systems

Subset of OpenGL for embedded devices/system, cross-platform, managed by the non-profit technology consortium Khronos Group

Supported platforms: iOS, Android, BlackBerry, bada, Linux, Windows
Below image shows how OpenGL ES evolved over years,

OpenGL ES API profiles(Specifications)

• OpenGL ES 1.x, fixed function pipeline, OpenGL ES 1.0 subset of OpenGL 1.3 and OpenGL ES 1.1 subset of OpenGL 1.5

• OpenGL ES 2.x, programmable pipeline, OpenGL ES 2.x subset of OpenGL 2.0

• OpenGL ES 3.x, programmable pipeline, OpenGL ES 3.0 subset of OpenGL 3.3

Reference:

OpenGL ES 3.0 specification 

OpenGL ES 3.0 Programming Guide 

OpenGL ES 3.0 rendering pipeline 

Low level 3D Graphic APIs

Application Programming Interface (API) standardized to give programmer/developer a low level interface (access and control) to graphic rendering system/hardware. 
Standardizing APIs increases portability and allows software developers to concentrate on creating quality products, on producing interesting content, and on the overall performance of their applications, rather than worrying about the specifics of the platforms they want them to run on.

Well known low level 3D Graphic APIs,

OpenGL, most widely used and supported 2D and 3D graphics (API), cross-platform, managed by the non-profit technology consortium Khronos Group
OpenGL ES, subset of OpenGL for embedded devices/system, cross-platform, managed by the non-profit technology consortium Khronos Group

Direct3D, low level 3D graphics APIs for Microsoft windows

Mantle, developed by AMD

Metal, developed by Apple

Vulkan, a low-overhead, cross-platform 3D graphics and compute API by the Khronos Group

Below image showing OpenGL, Direct3D(DirectX) evolution,

Below showing OpenGL 3D API Family Tree

Interesting articles on how OpenGL and DirectX evolved, some terms them as “war between OpenGL and Direct3D”

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