The format of a file is by default deduced from the file extension in its name, or by FileFormat from its contents.
Import elements determine which aspects of a file should be imported, and how they should be returned to Mathematica.
The following forms of element specifications can be given:
take the file to be in the specified format
import a single element assuming the default format
import an element assuming the specified format
assume also compression formats (e.g. "GZIP")
import subelement of
import subelements of subelements
import several subelements of
import the n part of
Types of elements typically supported include:
a list of names of elements
rules for the values of all elements
rules for options, settings, meta-information, etc.
data in a generic Mathematica form (list, string, etc.)
raw data as used in the format (e.g. indexed colors)
raster image (for graphical formats)
2D graphics (for graphical or geometry formats)
3D graphics (for graphical or geometry formats)
sound (for sound formats)
plain text (for textual formats)
grid format (for arrays, spreadsheets, etc.)
If no element specification is given, Import will typically return expressions that display or operate as much as possible as they would in an external viewer of the file being imported. Graphical formats, for example, are by default returned as Graphics or Graphics3D expressions.
For some formats, there are options that specify details of how the import process should be performed; these are given as Import.
When importing from a URL, Import can handle , , and .
Import uses proxy and related settings specified in Preferences settings in the notebook front end, or in your operating system environment.
Import generates a dialog if interactive authentication is required.
Import takes a "" option which controls how Mathematica authenticates the identity of a server when establishing a network connection. By default Mathematica uses interactive authentication if necessary. With a setting False, Mathematica connects to the server without authentication. With True, Mathematica only connects to servers whose authenticity has been previously established.