Fonts are styles of text that determine how letters and numbers look when printed or displayed on a screen. Each font has its own unique design, which can convey different feelings or messages. For example, a serif font like Times New Roman has small lines at the ends of letters, giving it a classic and formal appearance, while a sans-serif font like Arial looks more modern and clean. Choosing the right font is important for effective communication. It can affect how readers perceive the content. For instance, using a playful font for a children's book can make it more inviting, while a professional font is better suited for a business report.