International governance has become increasingly legalized throughout the twentieth century. However, legalization is not binary which international law is not simply present or absent in a given issue area and makes the situation much more complex. In respect of legalization above, a better approach is to understand legalization as continuum, moving from soft law to hard law.
Hard law refers to actual binding legal instruments and laws. In contrast with soft law, it gives states and international subjects actual binding responsibilities as well as rights. Regarding to the definition, to constitute law, rule, instrument or decision must be authoritative and prescriptive. In international law, hard law includes self-executing treaties or international agreements, as well as customary laws. These instruments result in legally enforceable commitments for countries and other international subjects.
Soft law refers to quasi-legal instruments which do not have any legally binding force or whose binding force is somewhat weaker than the binding force of international law which it is often contrasted with hard law. Soft law is associated with international law, although more recently it has been transferred to other branches of domestic law as well.
The term soft law covers such as elements as: (a) most resolutions and declaration of the UN General Assembly; (b) elements such as statements, principles, codes of conduct, codes of practice, etc. which are often found as part of framework of treaties; (c) action plans; (d) other non treaty obligations. While the term hard law covers such elements as: (a) treaties (conventions or international agreements); (b) Security Council resolutions; (c) customary international rules.
It is important to note that soft law instruments are negotiated in good faith by the negotiating parties who hold some expectations that the non-binding commitments will be met as much as reasonably possible. An important role of soft law instruments is their ability to influence the future developments of hard law commitments.