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Pseudo code expresses code logic in
procedures using plain verbs and

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nouns from spoken language.

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When you write pseudo code,
you explain each step in the program.

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Think of it kinda like a recipe.

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A program usually has some data,
or ingredients,

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that are acted upon just like you peel,
mix, whisk, eat and bake while cooking.

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A recipe lists the exact order
in which to perform each step.

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If you bake, for

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example, before you mix the batter,
your cake won't turn out right.

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You can write pseudo code on paper with
a pen, or open up a text editor and

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use code comments to describe your
program's logic in pseudo code.

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Let me walk you through an example.

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For any programming project, we usually
start with a set of requirements.

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These requirements,
like a set of instructions,

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tell you how the program should perform.

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They'll often want some input, like
retrieving two numbers from a user and

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some kind of output like the result
of adding those two numbers together.

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You can use those requirements to
guide the design of your program and

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the pseudo code you write.

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In this example,
we'll take a simple specification and

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convert it into programming
steps using pseudo code.

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If you'd like to follow along, open the
work space associated with this video, and

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the file print underscore sum dot txt.

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[SOUND] Get two integer values from a user
and output the sum of those numbers.

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In other words, get two numbers,
add them together and output the results.

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The requirement is simple, but

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a program would need to perform
several steps to complete the task.

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First, you need to prompt
the user to type a number.

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That's one step.

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Then you create a variable
to store the input.

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Prompt for another number, store that
number in a variable named num2.

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Create another variable with
the sum of the two values.

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And finally,
print the value inside the sum variable.

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That's an example of pseudo code.

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It reads easily and

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could be used by a programmer
coding in any programming language.

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This example is simple, but

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you can use pseudo code to
describe any programming concept.

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For example, here's how you could add
a conditional statement to make sure

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the input from the user was a number and
not a letter.

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Here, I've added conditional statements to
check and see if the input is a number.

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Notice that I've added indentation
to show the code that runs

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inside the conditional statement.

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In other words, if that condition is true,

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then the steps that
are indented would happen.

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To mark the end of a conditional
statement add endif.

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This makes clear where the condition ends
and the rest of the program continues.

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You can easily create conditional
statements with multiple conditions too.

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Pseudo code is simple and straightforward.

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You can easily see the logic and
you never get a syntax error.

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In the next video,
I'll show you pseudo code for

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describing other programming
concepts like loops and functions.