Attention to detail is not the only fundamental aspect of effective management in the modern business world. Besides ethics and providing a path for a brighter future, you also want to pay attention to creating a greener company.
Gone are the days where desks were hidden under towers of papers, especially considering that there is an extensive range of digital tools available for working with files.
Here is a guide on how to join your e-files in e-media rich documents, merging different types of formats like 
PDF, Excel spreadsheets;  merging custom subject lines and custom attachments, or if you need to distribute a document with a signature on the backside of the page. Well, wouldn’t it be easier to merge PDF online? Yes, and here are some of the reasons why.
Source: https://www.entrepreneurshipsecret.com/online-pdf-merge-tools/