一个小的输入， 我曾经遇到过响应式图像在iphone上的渲染速度减慢长达一分钟的问题，即使是小图像:

<!-- Was super slow -->
<div class="stuff">
    <img src=".." width="100%" />
</div>

但是当切换到使用背景图像时，这个问题就消失了，这只有在针对较新的浏览器时才可行。

One more benefit from using the <IMG> tag is related to SEO - i.e. you can provide additional information about the image in the ALT attribute of the image tag, while there's no way to provide such information when specifying the image through CSS and in that case only the image file name may be indexed by search engines. The ALT attribute definitely gives the <IMG> tag SEO advantage over the CSS approach. That's why according to me it is better to specify the images you want to rank well in the image search results (e.g. Google Image Search) using the <IMG> tag.

图像的大小呢?如果我使用img标记，浏览器将缩放图像。如果我使用css背景，浏览器只是从较大的图像中切割一块。

以上回答只考虑设计方面。我在搜索引擎优化方面列出了它。

何时使用<img />

When Your Image need to be indexed by search engine If it has relation to content, including cards (click areas), but not related to design. Design is probably the most difficult thing to parse here because so it's all design right. I would say perhaps functional design (Cards, thumbnails, profile images, things you can click) vs Aesthetic design which is mostly used for sites appeal. List item If your image is not too small ( not iconic images ). Images where you can add alt and title attribute. Images from a webpage which you want to print using print media css

何时使用CSS背景图像

纯粹用于设计的图像。 与内容无关。 小图像，我们可以玩CSS3。 重复图片(在博客作者图标中，每篇文章都会重复日期图标等)。

因为我将基于这些原因使用它们。这些都是图像搜索引擎优化的良好实践。

这里有一个技术上的考虑:图像是动态生成的吗?在HTML中生成<img>标记往往比尝试动态编辑CSS属性容易得多。

只在必要的时候使用背景图像，例如容器的图像是平铺的。

其中一个主要的优点是使用图像是更好的搜索引擎优化。