Alt text, short for alternative text, is a written description added to images on a webpage. It was first created to help people who use screen readers understand what an image represents, making websites more accessible. Search engines also rely on alt text because they cannot “see” images in the same way humans do. Instead, they read the text behind the image to understand its content. For example, if you upload a photo of a person skiing, an alt text that says “skier going down a snowy slope” describes the image clearly.
Good alt text serves two purposes. It makes content more inclusive for visually impaired visitors, and it provides search engines with important information about your page. This is why alt text is often mentioned in SEO discussions. If you leave it empty or use vague text like “image123,” you lose both accessibility value and search optimization opportunities. On the other hand, if you overuse keywords and force them into every description, it can look unnatural and even harm your ranking.
The best practice is to keep alt text descriptive but natural. Think about how you would explain the image to someone who cannot see it. One short sentence is usually enough. For websites with many images, such as e-commerce stores, alt text can make a huge difference. Each product photo becomes a chance to appear in image search and to provide context for your main keywords. While it is a small detail, alt text strengthens both usability and SEO, making it a simple but powerful habit to apply.
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