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+.. Objectives
+.. ----------
+
+.. At the end of this tutorial, you should know --
+
+.. 1. How to define strings
+.. #. Different ways of defining a string
+.. #. How to concatenate strings
+.. #. How to print a string repeatedly
+.. #. Accessing individual elements of the string
+.. #. Immutability of strings
+
+.. Prerequisites
+.. -------------
+
+.. 1. getting started with ipython
+
+.. Author : Madhu
+ Internal Reviewer : Punch
+ External Reviewer :
+ Language Reviewer : Bhanukiran
+ Checklist OK? : <15-11-2010, Anand, OK> [2010-10-05]
+
+Script
+------
+
+{{{ Show the slide containing the title }}}
+
+Hello friends. Welcome to this spoken tutorial on Getting started with
+strings.
+
+{{{ Show the slide containing the outline }}}
+
+In this tutorial, we will look at what we really mean by strings, how
+Python supports the use of strings and some of the operations that can
+be performed on strings.
+
+{{{ Shift to terminal and start ipython }}}
+
+To begin with let us start ipython, by typing::
+
+ ipython
+
+on the terminal
+
+So, what are strings? In Python anything within either single quotes
+or double quotes or triple single quotes or triple double quotes are
+strings.
+
+{{{ Type in ipython the following and read them as you type }}}::
+
+ 'This is a string'
+ "This is a string too'
+ '''This is a string as well'''
+ """This is also a string"""
+ 'p'
+ ""
+
+Note that it really doesn't matter how many characters are present in
+the string. The last example is a null string or an empty string.
+
+Having more than one control character to define strings is handy when
+one of the control characters itself is part of the string. For
+example::
+
+ "Python's string manipulation functions are very useful"
+
+By having multiple control characters, we avoid the need for
+escaping characters -- in this case the apostrophe.
+
+The triple quoted strings let us define multi-line strings without
+using any escaping. Everything within the triple quotes is a single
+string no matter how many lines it extends::
+
+ """Having more than one control character to define
+ strings come as very handy when one of the control
+ characters itself is part of the string."""
+
+We can assign this string to any variable::
+
+ a = 'Hello, World!'
+
+Now 'a' is a string variable. String is a collection of characters. In
+addition string is an immutable collection. So all the operations that
+are applicable to any other immutable collection in Python works on
+string as well. So we can add two strings::
+
+ a = 'Hello'
+ b = 'World'
+ c = a + ', ' + b + '!'
+
+We can add string variables as well as the strings themselves all in
+the same statement. The addition operation performs the concatenation
+of two strings.
+
+Similarly we can multiply a string with an integer::
+
+ a = 'Hello'
+ a * 5
+
+gives another string in which the original string 'Hello' is repeated
+5 times.
+
+Following is an exercise that you must do.
+
+%% %% Obtain the string ``%% -------------------- %%`` (20 hyphens)
+ without typing out all the twenty hyphens.
+
+Please, pause the video here. Do the exercise and then continue.
+
+::
+
+ s = "%% " + "-"*20 + " %%"
+
+Let's now look at accessing individual elements of strings. Since,
+strings are collections we can access individual items in the string
+using the subscripts::
+
+ a[0]
+
+gives us the first character in the string. The indexing starts from 0
+for the first character and goes up to n-1 for the last character. We
+can access the strings from the end using negative indices::
+
+ a[-1]
+
+gives us the last element of the string and
+::
+
+ a[-2]
+
+gives us second element from the end of the string
+
+Following is an exercise that you must do.
+
+%% %% Given a string, ``s = "Hello World"``, what is the output of::
+
+ s[-5]
+ s[-10]
+ s[-15]
+
+Please, pause the video here. Do the exercise and then continue.
+
+::
+
+ s[-5]
+
+gives us 'W'
+::
+
+ s[-10]
+
+gives us 'e' and
+::
+
+ s[-15]
+
+gives us an ``IndexError``, as should be expected, since the string
+given to us is only 11 characters long.
+
+Let us attempt to change one of the characters in a string::
+
+ a = 'hello'
+ a[0] = 'H'
+
+As said earlier, strings are immutable. We cannot manipulate a
+string. Although there are some methods which let us manipulate
+strings, we will look at them in the advanced session on strings. In
+addition to the methods that let us manipulate the strings we have
+methods like split which lets us break the string on the specified
+separator, the join method which lets us combine the list of strings
+into a single string based on the specified separator.
+
+{{{ Show summary slide }}}
+
+This brings us to the end of another session. In this tutorial session
+we learnt
+
+ * How to define strings
+ * Different ways of defining a string
+ * String concatenation and repetition
+ * Accessing individual elements of the string
+ * Immutability of strings
+
+{{{ Show the "sponsored by FOSSEE" slide }}}
+
+This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India
+
+Hope you have enjoyed and found it useful.
+Thank you!
+