PDF

PDF stands for "Portable Document Format: A universal file format that preserves the fonts, images, graphics, and layout of any source document, regardless of the application and platform used to create it"

To a 10-year-old, this means that PDF is a way to save things. It keeps everything the same.

Many online files are in the PDF format, such as tax forms. In order to read a PDF file, one needs a special reader provided by Adobe.