1. Introduction
2. Library of M-type CARMENES Spectra
2.1. Sample
2.2. Stellar Rotation
2.3. Absolute Radial Velocities
3. Spectral Atlas
4. Radial Velocity Information Content
4.1. Empirical Radial Velocity Information
4.2. Spectroscopic Information and Signal-to-Noise Ratio
5. Summary