English: Both serif and sans serif fonts have their own advantages and disadvantages. In the above diagram, first example shows serif fonts seem more efficient to distinguish I (uppercase ai) and l (lowercase eL), as in "Illusion" or "Illustration" or "Illinois" etc. and vice versa, sans-serif is less-efficient. But on the second example, sans-serif font seems more efficient to distinguish 1 (One, the numeral) and l (Lowercase eL) due to lack of any serif on l (lowercase eL). On the second example it is harder in serif font, to recognize whether it is "1Lamp" (One Lamp) or 11amp (Eleven Ampere).