1.  Constitutes the first and the most important form of international cooperation.It comprises: international economic and trade agreements, economic and technical aids such as loans,subsidies, credit facilities,incentives and facilities for investment,economic grouping (free trade areas).  Nowadays, international cooperation has increased to cover all fields and domains of international relations (Culture and security, political, labor and immigration……….)  The end of cold war witnessed the increasing of international cooperation and interdependence among actor in international relation.

2.  2)-the second form of international relations consists in relations and interactions based upon allying:  States enter alliances for many various purposes.

3.  A-Defense and deterrence.Alliances are used as means for defending the states parties against any aggression or armed attack.  Alliances also constitute a mean of deterring others from attacking or threatening any of the allied parties.

4.  B-Domestic means: Alliances can be used as a mean for supporting central governments against rebellions and opposition powers.  C-Foreign policy: Alliances can be used as a mean of foreign policy where the state party to an alliance uses it in exercising pressures and influence against other in order to achieve goal of foreign policy  Ex.The strategic alliance between several and the United States of America which is extremely exploited by Israel in realizing its policy towards the Arabs and the Palestinians.

5.  A)-Bilateral / Multilateral  -Bilateral alliance where state allies with anther.Ex.The strategic American Israeli alliance.  -Collective or Multilateral alliance where a group of states enter into alliance.Ex.North Atlantic Treaty Organization "NATO" which comprises. Western European countries and the United states of America in the post cold war period,some eastern European countries like Estonia,Latvia, and Chic joined the NATO alliance.

6.  -On the other hand Warsaw pact was a multilateral alliance which was created in the cold war era between the USSR the Soviet Union and European communists states in Eastern Europe. This alliance collapsed in 1991 with the end of the cold war.

7.  B) Defensive /Offensive:  Defensive alliance are built to guarantee the security of its parties and to defend them against any attach directed to any party the alliance.Because defensive alliance conform which international law rules which forbids the illegal use of force in international relations,they are usually open alliances.

8.  Offensive alliances are usually built to achieve offensive purposes where the parties to the alliance plan for attacking others.  Because offensive alliance contradict with international rules which prohibit the illegal use of force,they are security built.  That's why alliances call themselves in the contemporary international relations as defensive alliances.

9.  C)-Military /Diplomatic  -military alliances are hose alliances which are constructed to achieve military and security aims joint and mutual defense for all members to the alliance (NATO,and formally Warsaw Arab mutual defense treaty in 1950….)

10.  -diplomatic alliances are those alliances which aim at coordinating and consolidating the positions and policies of the parties towards issues and problem affecting them. International relations knows a lot of diplomatic alliances which are usually created among states having much in common but they don't have the military capabilities necessary for constructing military alliances.

11.  However, it can be noted that alliance may suffer from mis-planning,lack of coordination, internal divisions, preferring self interest to common interest to common interest of the members to the alliance …,factors which lead in the final analysis to the collapse of the alliance.  Ex.The collapse of Warsaw alliance due to the collapse of the Soviet Union in 1990.  *The ineffectiveness of Arab mutual defense agreement due to Arab divisions, rivalries, and lack of common awareness of common sources of treating and danger.