Question about jailbreak-help plz

[jolly123]

Hi guys
I wanna know that If befor jailbreaking i have been installed some applications,after jailbreaking what happen to them?they're ganna be removed?what about other datas like contact or messages, pictures...
Or after jailbreaking nothing happens to them?
By the way,i got 4S

 

[Jmills87]

Nothing will be removed unless you restore

 

[jolly123]

Thank you so much dude