IFRS vs US GAAP
Two accounting frameworks: IFRS, used in most of the world, and US GAAP, used by US domestic companies; they differ in several rules.
IFRS (International Financial Reporting Standards) is issued by the IASB and used in most jurisdictions outside the US. US GAAP is issued by the FASB and used by US domestic filers. Differences include inventory costing, since LIFO is not permitted under IFRS; the treatment of impairment reversals; and the presentation of leases.
Traders care because the same company can report different operating profit, inventory and leverage under each framework. Comparing foreign and US peers requires adjusting for these differences. Read the reconciliation notes and the basis of preparation section in the filing.
Worked example (illustrative numbers, not real data): a company reports 200 million dollars of LIFO reserve under US GAAP. A comparison on an IFRS basis would need inventory restated to a FIFO-type basis, which would raise inventory by about 200 million dollars.