Functional illiteracy is the inability to read or write well enough to accomplish everyday tasks in modern society. It is different from pure illiteracy, which is the inability to read or write at all. Functional illiterates may have basic reading and writing ability but cannot carry out more advanced tasks such as operating a computer, filling out a job application or completing a tax form. A 2007 study estimated that 860 million people worldwide are functionally illiterate.