What are the difference between IFRS and US-GAAP reporting system?

IFRS is considered more of a "principles based" accounting standard as compare to U.S. GAAP which is considered more "rules based." By being more "principles.

For Intangibles U.S. GAAP is recognized at fair value, whereas IFRS, it is only recognized if the asset will have a future economic benefit and has measured reliability.

For Inventory CostsUnder IFRS, the  LIFO method for accounting for inventory costs is not allowed. Under U.S. GAAP, either LIFO FIFO inventory estimates can be used.