Arm® NEON™ technology is an advanced single instruction multiple data (SIMD [1]) architecture extension for the Arm® Cortex®-A Series.
NEON technology is intended to improve the multimedia user experience by accelerating audio and video encoding/decoding, user interface, 2D/3D graphics or gaming. NEON can also accelerate signal processing algorithms and functions to speed up applications such as audio and video processing, voice and facial recognition, computer vision and deep learning [2].
Start reading the useful information and presentations on NEON technology available from Arm NEON technology official web site.
The article How to accelerate JPEG compression and decompression presents an use case accelerated thanks to the Arm NEON technology.
1. References[edit source]
Arm® is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere. 
Arm® is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.