In HTML, the low attribute is used within the <meter> element to specify the lower bound or minimum value of a range. The <meter> element is used to represent a scalar measurement within a known range or a fractional value.

Here's how the low attribute functions:

• Usage: The low attribute is optional and can be added to the <meter> element to define the lower end of the range.

• Value: It accepts a numerical value that represents the minimum limit of the range. This value should be within the range specified by the min and max attributes of the <meter> element.

• Purpose: The low attribute provides additional semantic information about the measurement represented by the <meter> element. It indicates the lower boundary of the acceptable or expected range for the measurement.

• Visual Representation: Depending on the browser and CSS styling, the low attribute may influence the visual representation of the <meter> element. It might be used to change the appearance of the meter, such as by altering the color or styling when the value falls below the specified lower limit.

• Accessibility: Utilizing the low attribute can enhance accessibility by providing context to users about the range of acceptable values for the measurement being displayed.

Here's a basic example demonstrating the usage of the low attribute:

<meter value="25" min="0" max="100" low="20">25 out of 100</meter>

In this example, the low attribute is set to 20, indicating that values below 20 would be considered low. The meter's visual representation might adjust accordingly to reflect this lower boundary, depending on browser and CSS styling.