Virtual PDF printers are probably the easiest way to create a brand new PDF file because they support, as source, any printable file. No matter if you have a Word, Excel, PowerPoint, a JPG image or other type, as long you can print it (Ctrl+P), you will be able to convert it in a fully editable PDF document.
There are different programs to create PDF from scratch, but is easier to work in Microsoft Word and then transform it into PDF with one or two clicks.
Because these are a very, very easy way to create a PDF document and because support almost all types of files as input, as long as they can be printed.
Besides converting, is good to have advanced features to customize the way how your PDF will be produced. These programs may look similar for all major features, but in fact there are many differences that could improve your productivity, such as the speed and file size.
Conversion Speed If you generate these files often or you work with big files, a faster PDF writer will save your time.
PDF File Size The best programs will produce files with a small file size. It is important to keep a small file size because some services such as online email clients can have file size limitations when you add attachments. Otherwise, you will need to find a way to compress or reduce the size of PDFs before sending.
Security & Privacy Is useful to have options to set a password, to restrict the printing or editing. The best printers allow to add watermark with custom position and digital signatures to check the integrity of the file (you compare the digital signatures and will know if the PDF was modified).