Anything smaller tends to look squeezed together to scanners and optical character readers, while a type that is too big tends to run together and blur. Boldface may not be accepted by all systems, but unless an employer tells you to avoid the use of boldface, it is accepted by most systems. Avoid script, italic, and underlined text. Avoid graphics or shading. Horizontal and vertical lines should be used sparingly.
Computers have difficulty trying to read the lines.
If you do use lines, it requires white space around it. Do not use parentheses or brackets around any telephone area codes. Most systems have no trouble reading the parentheses or brackets but some think it is best to leave them off. Avoid compressing space between letters. When you scrunch up your text, it becomes unreadable.