By removing or minifying code in your scripts it reduces the script size. Having smaller sized JS scripts and files means your visitors can load your web pages faster because they need to download less data when loading your web pages.
Yes, click on the UPLOAD & COMPRESS FILE(S) tab and choose the JS file you want to compress. Click on the red Select More Files link to upload more than one file. When you choose to upload and compress multiple JS files they will be combined into one bigger script.
Analyze your CSS to make improvements to the CSS Delivery.
Minimize CSS scripts and files for page speed.
Minify your JS files and scripts to maximize performance.
Check whether your web pages have Gzip compression enabled.
Tests your image delivery so you can improve it.
Reduce your PNG image filesize while keeping quality.
Play with the quality and size of JPEGs to save disk space.
Place multiple images in one image to make fewer requests.
Check how and whether your website files are cached.
Test your web pages for broken links and requests.
How many HTTP requests do your web pages produce?
Encode JPEG and other files into a Base64 string.
Check whether your website has keep-alive settings as enabled.
Remove line breaks from your scripts to save disk space.
Check the HTTP server header of your site.