Files and Streams
  Files and Streams
| name.m | Wolfram Language source file | 
| name.nb | Wolfram System notebook file | 
| name.ma | Wolfram System notebook file from before Version 3 | 
| name.mx | Wolfram Language expression dump | 
| name.exe | WSTP executable program | 
| name.tm | WSTP template file | 
| name.ml | WSTP stream file | 
Most files used by the Wolfram System are completely system independent. .mx and .exe files are however system dependent. For these files, there is a convention that bundles of versions for different computer systems have names with forms such as name/$SystemID/name. 
   
   - If the name starts with !, the Wolfram Language treats the remainder of the name as an external command, and uses a pipe to this command.
- If the name starts with http:// or https:// the Wolfram Language treats the name as a URL and reads the file from a web server.
- If the name is handled by a registered stream method, the method will open the stream using the name.
- If the name contains metacharacters used by your operating system, then the Wolfram Language passes the name directly to the operating system for interpretation.
- Unless the file is to be used for input, no further processing on the name is done.
- Unless the name given is an absolute file name under your operating system, the Wolfram Language will search each of the directories specified in the list $Path.
- If what is found is a directory rather than a file, then the Wolfram Language will look for a file name/$SystemID/name.
For names of the form name` the following further translations are done in Get and related functions: 
   | InputStream["name",n] | input from a file or pipe | 
| OutputStream["name",n] | output to a file or pipe | 
| option name | default value | |
| CharacterEncoding | Automatic | encoding to use for special characters | 
| BinaryFormat | False | whether to treat the file as being in binary format | 
| FormatType | InputForm | default format for expressions | 
| PageWidth | 78 | number of characters per line | 
| TotalWidth | Infinity | maximum number of characters in a single expression |