Maillard's reaction

Maillard’s reaction is one of the most important reactions in cooking. It happens when applying heat to the food: just the definition of cooking.

Reaction takes place between amino groups from proteins and carbonyls from sugars. Maillard's reaction produces the typical colors, tastes and flavors to toasted or roasted food when it is cooked with no water (boiling does not produce Maillard's reaction)

Maillard's reaction is not a unique reaction but a type of reaction, which depends on the kind of sugar and protein involved in the reaction. This is the reason to get different taste, brown colors and flavors depending on the food

Maillard's reaction is different to caramelization though both produce brownish colours. Caramelization takes places between sugars only, with no proteins involved in the reaction.
In both case, caramelization and Maillard's reaction are non-enzymatic chemicals reactions.

Maillard's reaction is faster and more intense at higher pH and temperature (above 150 Celsius).

They can, indeed, compensate to each other, e.g. higher temperature compensates lower pH and higher pH compensates lower temperature, producing in both cases similar effects.
The pH effect can be also used to stop the Maillard's reaction just adding any acidic substance like lemon juice, red wine or vinegar while still cooking inside.