European shares opened higher on Friday at the end of an extraordinary week of trading, taking heart from the gains on Wall Street on Thursday.
In early trading the FTSE 100 rose 4.3%, the Dax in Frankfurt was up 4% and the Cac 40 in Paris was up 4.6%.
It followed gains of 4.7% in New York and 2.8% on Tokyo's Nikkei 225 index.
The mood was helped by news from IBM, which said it expects to meet long-term profit forecasts and Google, which reported better-than-expected results.
But concerns remain about the state of the global economy.
Oil prices rose above $72 a barrel from a 14-month low as investors bet that fears that demand for energy would be hit by the global downturn were overstated.
Key indexes in South Korea and Australia fell back slightly, though markets were relatively stable in comparison with recent gyrations.
The Nikkei index climbed 235.37 points to end at 8,693.8, having lost more than 11% on Thursday.