Tomme is a generic name given to a class of cheese produced mainly in the French alps. Tommes are normally produced from the skimmed milk, left over after the cream has been removed to produce butter and richer cheeses, or when there is too little milk to produce a full cheese. As a result, they are generally low in fat.
There are many varieties of Tommes, which are usually identified by their place of origin. The most famous of these is Tomme de Savoie. Other Tommes include Tomme Boudane, Tomme au Fenouil and Tomme du Revard.
Tomme is traditionally used to make aligot, an Auvergnat dish combining the melted cheese and mashed potatoes.
Aligot is a dish traditionally made in the Auvergne region of France made of melted Tomme cheese blended into mashed potatoes, often with some garlic. Other cheeses - usually not fully ripe - can be substituted for Tomme cheese. The dish is ready when it develops a smooth, elastic texture.
This dish was originally made from bread by monks who prepared it for the pilgrims on the way to Santiago de Compostela, but potatoes were substituted after their introduction to France, because they allowed a more desirable consistency.
Danish web site here: with information on French cheeses (including which wine to drink with them) [in French, Danish or English]