Huge "Data" when using DiskUsage in Innternal Memory My Lenovo P770's internal memory usage is very large – although I have deleted some unimportant data/apps. This is what it looks like using DiskUsage application:


Screenshot (click for larger variant)

I noticed that theres a huge "Data" (755 MB) in my internal storage. 
What is this data? Is it save to delete it? How to do it (where is it's location)?

Sorry for much questions, please help me out. Thanks a lot

Note: I have used CCleaner but it doesn't help much. I think the main problem is this huge "Data".
As you can see on the right, it contains the private data for all apps. If you want to delete these data, you can do it by uninstalling apps or by clicking "Clear data" in the apps manager.