Q. Define the Real wage?
Consider the following scenario. You work full time and during January 2008 you make 2000 euro after tax. A certain basket of goods and services costs 100 euro in January that means that your salary will buy you 20 such baskets.
In February, you receive a 10% wage increase and you make 2200 euro after tax. Does this imply that you can purchase 10% more baskets - which is 22 - in February? Well, not essentially.
Number of baskets that you can purchase in February depends on the possible changes in prices as well. If price of a basket increases by 3% to 103 euro your 2200 will buy you 2200/103 = 21.36 baskets of 7% more than in January. Albeit your wage has increased by 10%, you can only increase your consumption of baskets by 7%. We say that real wage has increased by 7%.
Officially, we define real wage as the nominal wage divided by a price index (characteristically CPI). In the instance above, your real wage was 20 in January and 21.36 in February if we use the price of basket as a price index. Remember that nominal wage will tell you your wage in units of currency whereas the real wage will tell you your wage in baskets of services and goods and this is more significant to us.
So we care about increases in real wages not in the nominal wages. If you found out that Ken who works in another country, got a 50% increase in his wage every year, you can initially be quite happy for Ken. If you then found out that inflation in country where Ken works is 70%, you should actually feel sorry for him. His real wage is 1.5/1.7 = 88% of his real wage year before - a real wage cut by 12%.