Freeze Headers for Scrolling
Working with a massive data set in a spreadsheet can be difficult, especially as you scroll up/down or left/right and the rows and columns may be hard to track. There's a simple trick for that if you've got a header row or column, where the first row/column has a descriptor. You freeze it so when you scroll, that row and/or column (or multiple rows and/or columns) don't move.
Go to the View tab and look for Freeze Panes. You can easily just freeze the top row (select Freeze Top Row) or first column (select Freeze First Column). You can do both at once by clicking the cell at B2 and just selecting Freeze Panes. This is where it's fun—select any other cell and also Freeze all the panes above and left of it. Select cell C3 for example and the two rows above and two columns to the left won't scroll. You can see it in the screenshot above, indicated by the darkened grid lines.
When you want to get rid of the freeze, you can just select Unfreeze Panes from the menu.