It must be the wintery weather — my mind is on freezing things. 
When you freeze a pane on an Excel spreadsheet, you're keeping a row or a column still while the rest of the cells below it can scroll freely. This step lets you view your column and row headings continuously while you scroll your document. This is great when you have a spreadsheet with enough data that you have to do a lot of scrolling to see all the cells, then lose track of the headers that label the columns.
Take 15-minutes to watch this demo to learn...
- How to freeze & unfreeze rows and columns
- How to print frozen rows or columns
- The difference between freezing panes, locking cells, and splitting the window
- Other tips that let you see and work with data more easily
Note: if you'd rather read how to do it rather than watch the video, here are links to the resources Dave demonstrates:
- Freeze panes to lock the first row or column (how-to)
- Freeze rows and columns (how-to)
- Unfreeze locked panes (how-to)
- Freeze panes to keep headers in site (video for Excel 2010)
- Split panes to lock rows or columns in separate worksheet areas
Here's a link to the above video, in case the embedded video doesn't play for you.
Photo credit: Alison Taylor via Stock.xchng