It would be extremely difficult to see a pattern or trend in your data if you have thousands of rows or columns of data. This is where conditional formatting provides another way to visualize data and make worksheets easier to understand and read.
Conditional formatting allows you to automatically apply formatting—such as colors, icons, and data bars—to one or more cells based on the cell value.
TO APPLY CONDITION FORMATTING
1 - Select the cells which require the conditional formatting
2 - From the Home Tab select Conditional Formatting, a drop down menu will appear
3 - Select the desired rule from the menu that appears
There are many Conditional Formatting options available which include; Highlight Cell Rules, Top/Bottom Rules, Data Bars, Colour Scales and Icon Sets