Before we look at alignment, we need to look at text wrapping. Wrapping text in cells is a key feature in Excel. Wrapping text allows you to fit multiple lines of text in a single cell.
Let's take a look.
You've probably noticed that longer text will extend right through the cell border into columns to the right, as long as those columns don't contain data. If those columns do contain data, the text will be cut off at the cell border.
There are a couple of ways to handle this in Excel. One obvious solution is just to make the column wider. You can adjust the column manually, or, you can double-click the column border to automatically expand the column to fit the widest entry.
However, this isn't really an option when you have a lot of other columns to display.
A better solution is to wrap the text in cells that contain more content. Excel provides a "Wrap Text" button in the Alignment group on the home tab of the ribbon. This button toggles text wrapping on and off.
You can also control text wrapping from the Format Cells dialog box. When Wrapping is on, you'll see the Wrap Text checkbox checked on the Alignment tab.
Note that if you have selected multiple cells that have different text wrap settings, the Wrap Text checkbox will be filled in solid to indicate mixed settings.
Also be aware that text wrapping behaves differently depending on the width of the column. If the column is already wide enough to fit the longest entry when you enable text wrapping, nothing happens, even when you make the column too narrow to fit the text.
To get the text to wrap, you can either double-click a row border to get the row to resize, or you can just toggle Wrap Text on and off again.