Dome feature in SOLIDWORKS
A tutorial about nice feature called dome in SOLIDWORKS.
Go to Insert-->Features-->Dome,or just type Dome on the search bar.
Here I have a model and I have selected top face and you can see how bump is created.
If you turn off continuous dome you will get a shape like this.
I f you change the direction of Dome it will go inside and it will form a nice "hole".