We know that we can protect a worksheet so that user should not able to touch any of values in cell. You can protect the sheet by going to Review Tab --> Protect Sheet option. The option is shown in the following screenshot:
This is easy. But what if we want to allow user to enter data in some of the cells. Or if we want to open few of the cells to the user where he/she can enter his/her inputs.
Protection on a worksheet works only for those cells which are Locked. By default, every cell in a worksheet is locked so when a user protects a worksheet, all of the cells are locked by default. Vice versa, if a cell is not locked then user can edit the data even if the worksheet is protected. So to allow few of the cells to be unlocked(so that these can remain unprotected), we first need to remove the locked option from the cells. Following are the steps given to achieve this :
--> Select the cell which you want to unlock
--> Right click on that cell and click on Format Cells. It is displayed in the following screenshot :
--> Go to the protection Tab, and uncheck the "Locked" option. See the following screenshot:
If you keep this option unchecked for a cell/range, the cell/range cannot be protected. So if you want to keep few of cells open for user in a protected sheet, you can use the above mentioned procedure.
Hope this helps :)