How to make a Central database for mul pc's in same network?

Nowits time to run this Application to- all of each 7PCs in my Lab with a central databse where from it will communicate or,  supply[for Showing data, Add/Delete data] same data from any of 7PCs whenever i want to useit in my App.

how to make this central database for all pc's in my same network?

Note:
* Want to create in my same network
*Its unpublished yet,
*My current data source is: Data Source=SOLUTION-PC\SQLEXPRESS

Thanks :)