The term "horizontal line" is used in finance and economics as the x-axis in the chart. We proceed with this line from left to right. The term comes from geometric analysis, where this line is widely used alongside the vertical line (y-axis).
In technical analysis, the horizontal lines represent the part of the charts. A chart shows the movement of prices over time, with the horizontal axis showing the time scale and the vertical axis showing the price scale. You can insert additional horizontal and vertical lines into the chart. The vertical ones are used to determine the time when the candlestick appears. The horizontal lines, in turn, serve as a necessary trading instrument that helps a trader determine support and resistance levels.
Horizontal lines are used in horizontal analysis, which compares the value of prices over time. This may be helpful for a fundamental analyst who compares reports or statements over time. Time acts as the x-axis here and allows for the calculation of percentage changes over time.
Horizontal lines are also part of supply and demand curves, with the price on the vertical line and the quantity demanded on the horizontal line on a graph.