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- Welcome to lesson
three, control statements.

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One of the things that you're going to see

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as you get into Python

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is that it's a smaller
programming language

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than some of the other C-based languages

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you may be familiar with.

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You'll start to see that here

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in the control statements lesson

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because we have fewer
overall control statements

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than we do in those other
programming languages.

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Here we're going to start
out by taking a look

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at the three different
forms of the if statement;

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for making a single selection,

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for choosing between
two different actions,

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or for choosing among
many different actions.

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One of the things you'll notice

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as you look at the bullet points here

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is that you don't see anything
called a switch statement

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or a select statement like you may have

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in some of those other
programming languages.

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All of that is done in the context

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of the multiple selection

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if, elif, else statement.

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We do have some interesting
pattern-matching capabilities

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that we can use with that in Python,

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which gives us all the
features that we need

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from those statements in
other programming languages.

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We're going to take a look

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at the augmented assignment operators

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as part of this lesson.

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You're probably familiar with things

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like += from other programming languages.

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Perhaps most importantly,
we're going to take a look

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at the for statement in Python,

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which is for iterating
over sequences of elements.

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Basically for each item in
a sequence, do something.

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Unlike all of the other
C-based programming languages,

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Python does not have a
counter-controlled for loop.

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What we're going to do as
we introduce the for loop

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is first, we're going to
share you how to iterate

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over a sequence, like the
characters in a string,

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and we'll also introduce
as part of this lesson

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for the first time, the
Python list data structure.

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We'll iterate through items in a list,

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but we're also going to demonstrate

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how you can generate
a sequence of numbers,

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which is how you would, in turn,

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do counter-controlled iteration.

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There's a nice built-in
function called range

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which is capable of generating
sequences of integers.

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If I wanted, for example,
to do a test 10 times,

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I could say to do that
for each of the elements

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in a range of integers
from zero through nine,

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just as a for example.

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We'll also demonstrate
sentinel-controlled repetition

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in the context of the
while repetition structure.

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You will notice, by the way,

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that you do not have a do while statement

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as you do in many other
programming languages.

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We'll introduce the
boolean operators here.

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We have the and operator, the or operator,

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and the not operator.

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Those are all keywords of
the language in Python.

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They're not symbols like many of the other

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C-based programming languages.

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We'll introduce the break
and continue statements,

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which work exactly the same way as they do

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in the other C-based languages.

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However, unlike things like Java and C#

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where you have labeled break
and continue statements,

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we do not have those

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in the Python programming language.

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Finally, we'll take a look at a table

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of the functional-style
programming capabilities

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that we'll be presenting
in subsequent lessons

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and where you'll encounter those

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in those subsequent lessons as well.