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Welcome to this tutorial on the data types strings in Python.

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String is a sequence of Unicode characters in Unicode was introduced to include every character in all

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languages and bring uniformity in encoding.

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And strings in Python can contain as many characters as you wish.

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The only limit is your machines memory resources Python does not have a character data type.

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Like other programming languages.

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A single character is simply a string which has a length of 1

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and strings in Python can be created by enclosing inside single code or double code

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so if you enclose this text in Edo single code or double code.

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This is considered a string in python c is the case for this text now.

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Consider this text.

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It's a long work.

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Now in order to be considered as a string in Python I'm going to enclose this text in single code.

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It's a long walk so as but a discussion we have said that a string is something that can be enclosed

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in a single code or double quote.

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And once the Python interpreter read this text these string opens with a single code and the Python

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interpreter assumes the next single code in the text is the closing delimiter.

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The single code to your the final single code is then tree and causes a syntax error.

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So let's see this in the Jupiter notebook.

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So here we have our Jupiter notebook open and I have defined a string as these are one and the it points

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to the text.

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It's a long work and it is enclosed in single quotes Mullett executed this line and the code has been

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interrupted with the syntax error Invalid syntax.

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That's because the final single code is a straight and this is causing the syntax error.

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So in order to avoid this error what we can do is we can enclose this string in double quotes so let

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enclose the text in double codes and now print it out.

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So there is no error here.

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If there is a single code which is used within a string then we can delimit the string with double quotes

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and if there are double codes that are used within the string.

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In that case you can use the delimited single code

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now coming back to strings we can access individual characters using indexing.

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So what is indexing

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so for example I've defined a string E with the text.

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Now I would like to retrieve the third character in the string.

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The third character is B.

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So how do we do this.

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This can be done using indexing

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index start from zero and get incremented with each individual character in the string.

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Now in order to leave the letter B the format is

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E O squared.

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Brackets and the index number or the letter B which is to

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here it is the syntax for indexing is the variable which is pointing to the string happy and the index

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number is enclosed in square brackets and your rewrite the index number within the square brackets.

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Let's check indexing in the Jupiter book.

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So I've defined a where you've been e happy which is a string executed.

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Now I would like to index or retrieve the letter B which has an index to so within this grade bracket

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I'm going to do but the number two

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and to the letter B has been to.

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And this is the syntax for indexing the variable a is pointing to the string happy and then the index

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number is surrounded by square brackets in this retrieves the letter B.

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If you try to access a character out of range then it will raise an index error.

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So let's say variable is pointing to the string happy which contained so five characters let's say eight

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or six let's see what the interpreter does so since there are only five characters in the string a it

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has drawn the index into

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and also the index must be an integer we can't used flawed or other types.

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This will result in two or type error so giving plot numbers or any other data types results in type

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error Python allows negative indexing for it sequences the index of minus one refers to the last item

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minus 2 to the second last item and so on

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say for example we want to retrieve the letter B again using negative indexing we can do minus three

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in this grade bracket and at the same as e all do so let's check this in the Jupiter non book

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let's do a full minus three so the same letter has been on the tree lit so to the next

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letter B so that would be minus two.

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This is about a nixing.