It is the Y-axis or an index line, depending on where it is in the chart.
A vertical line!
A vertical line has an undefined slope. For the line to be parallel to a vertical line, the slopes would have to be the same. Therefore, the line parallel to a vertical line also has an undefined slope.
A horizontal line is a line perpendicular to the vertical.
VALUE
A broken line. - - - - -
move handle
Lines show on the page to indicate where the breaks are.
dotted red line
A dotted line.
vertical dotted line
vertical dotted line
The actual lines are known as gridlines, both vertical and horizontal. A vertical line of cells is known as a row.
You can put in dotted border lines. The regular lines that show rows and columns are known as gridlines, though they are solid, not dotted. Borders are set by the user and can be put in with different styles.
It is the Y-axis or an index line, depending on where it is in the chart.
It allows you to change things like the line's colour and thickness. You can change the line from being solid to other styles like dotted or dashed. You can change a line into being an arrow.
There are different types of lines: curved lines, dotted lines, wavy lines and straight lines.