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2.1.2 Interactive Mode

When commands are read from a tty, the interpreter is said to be in interactive mode. In this mode it prompts for the next command with the primary prompt, usually three greater-than signs (‘>>> ’); for continuation lines it prompts with the secondary prompt, by default three dots (‘... ’). The interpreter prints a welcome message stating its version number and a copyright notice before printing the first prompt:

    python
    Python 2.5 (r25:51908, Nov 18 2006, 11:52:11)
    Type "help", "copyright", "credits" or "license" 
    for more information.
    >>>

Continuation lines are needed when entering a multi-line construct. As an example, take a look at this if statement:

    >>> the_world_is_flat = 1
    >>> if the_world_is_flat:
    ...     print "Be careful not to fall off!"
    ... 
    Be careful not to fall off!