Ok techno geeks and computer pervs can you please help me understand

Nothing too technical - I am after all a gerl

but simple things
Like why , when I haven't use my computer ( laptop ) for over a week, do I turn it on this morning and all the settings are fecked.
The display properties, the layout of my desktop icons ( which are set up very particulalry to my liking ) etc . I logged off normally .
In Miss D's world of ...if no one ain't touched it then it should be exactly the same reality ....the time it has been left on it's own should have no impact on the bloody thing.
There hasn't been any upgrades of the system either ( if only

)