: Instead of downloading it to your local drive, you can use a PDF Viewer or pdfFiller to see the content in a sandboxed web environment.
: Government forms, legal contracts, and financial reports.
Could you provide more on where you found this file or what you expect it to contain? Knowing the source would help in identifying it. What is a PDF? Portable Document Format | Adobe Acrobat
: Before opening the file, right-click it and select Properties (Windows) or Get Info (Mac) to view metadata such as the author, creation date, and the application used to create it.
If you are looking to understand or "piece together" what this file might be, here is how you can safely handle and identify such documents: How to Safely Identify the File