A Triple Entente refers to an alliance uniting three identities.
The military alliance of France, the United Kingdom and Russia, referred to as the Triple Entente as opposed to the Triple Alliance, is in fact the combination of several agreements between the three countries.
First there was a military convention between France and Russia on August 17, 1892, then a Franco-Russian alliance on December 27, 1893. A few years later, on April 8, 1904, France and the United Kingdom sign the Entente Cordiale, a treaty of mainly symbolic significance (defines areas of influence concerning the colonies, in order to avoid incidents of the Fashoda type) which marks a diplomatic rapprochement between the two countries. Finally, the United Kingdom and Russia also define areas of influence, in Afghanistan and Iran.
The various agreements between the three protagonists were brought together and signed on August 31, 1907, thus giving birth to the Triple Entente. This alliance of the outer edges of Europe, which faced the Triple Alliance, was one of the elements that led to the First World War.