The “day grid” is the grid that shows up in your Calendar when you are looking at your Calendar in “Day” view and "Week (Column)" view. The day grid will show times in regular intervals for a specific length of time. See an example below:

You can choose what intervals your Day Grid displays in (15 minutes, 30 minutes, 1 hour, etc). But sometimes this means that your Day Grid slots are still too narrow to show all of the information for your events. In this case, you can choose to change the height of the Day Grid slots based on lines of text: 2 lines, 4 lines, 6 lines, and 8 lines. See the image below:

Changing the height of the Day Grid slots allows you to keep the time intervals you want, but there will be more room to display all of your event text.

To choose the line-height of your Day Grid slots follow the steps in the image below: