shutter Speed question

I often see shutter speeds saying for example 3999/100000 could some one tell me what speed this is or why this shows like this in the exif data of many pictures I look at ..

Thank you guys and gals

1/25th of a second.

That would be 1/25 or to be precise:

1/25.006251562890722680670167541885

I don't know why cameras record it that way. It tends to be cameras with highly variable electronic shutters and P&S cameras.

EDIT:

By the way, you have some very good shots of the Tamar valley. Just having a browse through your photos.

Thanks mr pentaxian and also Thank you Tyr .. I have a few more on my site I think and a few thousand on my HDD - Easy when I live right on top of it

-Pete-