Web front-end page performance optimization

Some commonly used optimizations:

1. Encourage front-end development engineers to achieve structural semantics when writing xhtml (the benefits of tag semantics: 1. Conducive to search engines; 2. Clear structure facilitates teamwork; 3. Conducive to blind screen readers. As for how Semanticizing labels depends on personal understanding. I also feel vague about this aspect, and it probably has something to do with personal habits.)

2. Optimization of the number and size of css and js files (generally, it is recommended that css and js be externally connected to reduce repetitive code and code reuse).

3. Optimization of the number and size of background images (use images in PNG8 format combined with css sprites. A large number of background images will affect the server and increase the number of http requests.).

4. Put the style sheet at the top; put the script at the bottom of the page; use instead of @import.