Central Bank Intervention in the Markets
They have different motives to their actions from the other playeres in the market, as they do not do it to make profits - the most profound change there can be really!
They often act in the markets in order to protect a particular currency, and sometimes they even do this knowing that they have a good chance of making a loss as a result.
There are also different attitudes within countries with regard their currency. Some like to see it quite strong all the time and have a steady value.
However countries for which exports is particularly important might actually be quite pleased to see devaluations occur to their currency, because clearly this makes their exports a lot more attractive to foreign sources as they get more bang for their buck, as it were.
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