A proton NMR spectrum reveals:

1. The number of proton environments.
2. The types of proton environment present.
3. The relative numbers of each type of proton.
4. The number of non-equivalent protons adjacent to a given proton.

The number of peaks in the ¹H NMR spectrum corresponds to the number of unique proton environments in the molecule.

The chemical shift range that a peak appears in indicates the type of proton environment. Different ranges correspond to different functional groups.

Spin-spin splitting patterns reveal the number of non-equivalent protons on adjacent carbon atoms.

For a proton with n protons attached to an adjacent carbon atom, the number of sub-peaks in a splitting pattern = n + 1

For example, a peak split into three (i.e. a triplet) indicates there are two hydrogens on the neighbouring carbon atom. 

A deuterated solvent is one in which the ¹H atoms have been replaced by ²H atoms.

The ²H isotope of hydrogen is called deuterium (D).

The ¹H atoms in a regular solvent produce signals that can interfere with the spectrum of the sample being analysed.

Deuterium does not produce any signal in the frequency ranges used for ¹H, so this interference is prevented and a higher resolution of the sample's spectrum can is obtained.

CDCl₃ is a commonly used deuterated solvent in NMR spectroscopy.

¹H NMR spectra are more complex than ¹³C NMR spectra due to the presence of spin-spin coupling between hydrogen atoms which causes NMR peaks to split into sub-peaks.

The relative peak areas are proportional to the relative numbers of equivalent protons producing each signal.