Adjusting column width
The simple reason behind adjusting your columns width is plain aesthetics. You want your workspace to look clear and easy to read.
You don’t want to have too much white space around your data, neither you wish to have your text "trimmed" by adjacent cells.
Let’s say, for instance, you have a column containing small numbers. In this case, you can quickly narrow its size and make it fit the content. On the other hand, if you have a column that stores addresses or full names, I would suggest you expand the size of the column in order to have the text fit neatly inside it.
Simple! Just drag the side edges of any column header if you want to do it manually, or double-click the side edge if you want it automatically adjusted. If you do it automatically, Excel will match the width of the column with the width of the cell with the largest content.