If you use high-quality photos in your PDF’s you will realize that they can get enormous. Well, have no fear, because there is an easy way to optimize your PDFs so they are as small as possible.

If you email someone and your PDF is larger than 10-20MB often other email systems won’t accept the attachment. One way to make sure that your attachment gets through is to make sure it is less than 10MB. One way to do this is to use the Adobe optimization tool for PDF – https://www.adobe.com/acrobat/online/compress-pdf.html
What this does is take your PDF and automatically optimize it. I worked with a graphics designer today who optimized her PDF to 15MB. I thought it could go smaller so she ran it through that service. It shrank from 15MB to 12 MB. Even optimized PDFs can get smaller by using this tool.
Now why would you want to optimize something twice? Optimization is a rapidly evolving thing and can be complex, especially for longer documents. There isn’t a one size fits all approach. In addition, even if you are an expert, having a second opinion of your efforts doesn’t hurt. Finally, this can be a quick way to optimize something without spending extra time learning about optimizing PDFs.
It was 20 years ago when I started using PDFS and even then there were tricks to optimize a PDF. No matter how much you know, the field of IT is always growing. So why not take advantage of the work other people have done as well? I believe in not reinventing the wheel, so if there is a supported way to do something then I am going to do that first and then get creative if that doesn’t work.
Why else are small PDFs important? On a webpage, a smaller PDF means that it will be easier for your customers to download. It will be easier for them to open and less likely to cause problems for their limited computer. Perhaps they are using an iPad and a smaller PDF is a much better experience. You can’t assume that because it is on the web, that is the only place it is going to be viewed.
Optimization matters even for things as common as PDFs.