This document contains a summary of an introductory session on Kotlin programming. It defines Kotlin as an open-source language that targets the JVM, Android, JavaScript and Native platforms. It notes that Kotlin code is shorter and more readable than Java for the same problems. The document discusses variables, data types, functions, and differences between var and val keywords in Kotlin. It provides examples of printing, defining variables, adding comments, defining functions, and passing parameters to functions.

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Camp Composed
Session 1 - Intro to Kotlin
September 19th

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Navaneeth K U
GDSC CCE App Development Lead
Session Lead

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Welcome App Developers!

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Kotlin is an open-source statically typed
programming language that targets the JVM,
Android, JavaScript and Native. It's developed
by JetBrains. It can be used on multiple
platforms
What is Kotlin?

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It has a much simpler and shorter code than
Java's code for the same problem. As this
makes the language more human-readable, it
becomes easy to debug. Kotlin's code is much
smaller and streamlines the programming process,
in comparison to Java. It has null safety feature
built-in.
Why Kotlin?

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The size of the Kotlin app takes less size as
compared to Flutter. Since Flutter is a UI tool,
so it needs third-party libraries and tools to
bridge a connection with the native
environment. It does not require third-party
libraries and tools to bridge a connection with
the native environment. Kotlin has better
performance than Flutter
Why Kotlin over Flutter?

7. Syntax
This work is licensed under the Apache 2.0 License

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println()
println(), print() are the printing
statements in Kotlin.
print() for just printing on the screen
println() for appending a newline
at the end

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Variables
In computer programming, there's the concept of
a variable, which is a container for a single piece
of data. You can envision it as a box that contains
a value.
The box has a label, which is the name of the
variable. By referring to the box by its name, you
have access to the value it holds.

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Variable format

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Use
Variables are used as placeholders in an
app which are replaced by information
You must declare a variable before using
it!

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Example:
Here, { Name } is a variable
These article cards are made
By populating the variables
With useful data!

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Data Types in Kotlin

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Variables
You can use variables in a string using
string interpolation
Output

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Variable coding convention

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Comments
When coding, another good practice to follow is to add
comments that describe what the code is intended to do.
Comments can help people who read your code follow it
more easily. Two forward slash symbols, or //, indicate that
the text after it on the rest of the line is considered a
comment, so it isn't interpreted as code.
It's common practice to add a space
after the two forward slash symbols.

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Comments
Single Line
Multi Line

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Functions
• A function is a block of code which
only runs when it is called. You can
pass data, known as parameters, into
a function. Functions are used to
perform certain actions, and they are
also known as methods.

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Functions
• Syntax

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Functions
• Syntax

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Functions
• Example Output

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• Function with return type

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Parameter Passed

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Example

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Variables
• var is used when you expect the
variable to change
• val is used when you do not expect
the variable to change
There are increment, decrement
operators just like in C language

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THANK YOU!