International Financial Reporting Standards, is a world-wide accounting standard formed under the IASB (International Accounting Standards Board).
While IFRS is a world-wide standard for financial records, statements and accounting, it is not commonly used in the United States. The United States prefers GAAP (General Accepted Accounting Principles).
IFRS has some key differences between GAAP. One difference is that IFRS is a principle based system, and GAAP is rule based. What that means, is that the IFRS applies accounting principles in ways that are more open to interpretation. Rule based accounting principles (such as GAAP) have less interpretation as they are quite explicit.