Answer:
The system of alliances was a complex network of agreement among the European powers to maintain peace, security and balance of power.
There were two main alliances:
- The Triple Entente, which consisted of Russia, Britain and France.
- The Triple Alliance, which consisted of Germany, Austria-Hungary, the Ottoman Empire, Italy (which later left) and Bulgaria.
These alliances assured that if one country were attacked, it had plenty of allies to depend on.