The PDF file was developed by Adobe Systems who intended to design a file format that can be displayed the same way on every computer. Today the PDF is the number one file format for sharing documents. Invoices, for example, are always received as PDFs. The PDF stands as the final result. Subsequent modifications are not possible. The file format was not designed for that purpose.
You can open a PDF file with a PDF reader. An example of a comprehensive program is Adobe Reader. However, there are a variety of other PDF readers that you can open a PDF file with. Today you can also open a PDF file without a PDF reader. Most browsers are already equipped to support PDF files, so you can easily open a PDF file using a browser.
You can create a PDF file with the free program PDF24 Creator. With the PDF24 Creator you can create PDF files from anything what is printable. The program is easy to use and is one of the most widely utilized tools in PDF creation. Install the software and always print using the PDF printer when you require a PDF.