• Easy to learn the basics.
• Clean and Concise syntax.
• Interoperable with Java(means each and every Java package or library or framework or API will work seamlessly with Kotlin), plus you might know how much big the Java ecosystem is.
• Provides nullable and type safety(means you don't need to write a whole try-catch block for catching null pointer exception because it can be handled safely, and type casting is also much safer).
• Strong type inference.
• OOPS with added modern features.
• Functional programming(FP) is at its best, it is used to write more concise, cleaner and better code, and if we mix OOP and FP in Kotlin, we can even make very amazing DSLs.
• Excellent and extended Java standard library.
• Coroutines(and structured concurrency).
• Wide range of apps can be made like multiplatform mobile, android, desktop, full-stack web apps and much more.
• Can also be compiled to JS and interop. with it, thus Kotlin uses existing JS APIs to make frontend web apps, there are plans that Kotlin will even work seamlessly with Node JS in future.
• Most preferred language for Android development with first-class support by Google.
• We can make Kotlin Multi-platform Mobile(KMM) applications that run natively on Android and iOS, by sharing common business logical code, leveraging existing APIs and keeping UI/UX native on each platform.
• KMM is a SDK that can also be added to an existing Android app to make it cross-platform.
• High speed UI development with Jetpack Compose(for Android) and Compose Multiplatform(for Web and Desktop).
• Can be used for data science and visualization, and deep or machine learning.
• Kernel for Kotlin can be added in the Jupyter notebook.
• In Kotlin, even primitive types have their own classes, and you can even add your own methods to them using extension functions without doing any inheritance.
• Kotlin is open-source and free to use, and there are many 3rd party libraries for Kotlin.
• Kotlin can be added in any Java IDE(although, IntelliJ IDEA is most preferred for Kotlin).
• Kotlin can be easily integrated and work parallelly with any existing Java ecosystem or project(s).
• Kotlin can interop. with C and Obj-C for iOS and other native app development(s), as Kotlin can be compiled to native binaries using LLVM, also special WebAssembly support will be soon added in Kotlin.
• Kotlin-Native and KMM plugin is available in Xcode IDE for making iOS apps using Kotlin.
• Kotlin Coroutines are lightweight than Java Threads.
• Kotlin Coroutines are multi-platform, means they can be used when you are targeting JVM or JS or Native platforms using Kotlin.
• Kotlin can run as a script too(that eventually replaces the need of bash or groovy-gradle scripts).
• Kotlin has a big, friendly and helpful community.
• Kotlin is adopted by many major institutions and universities as a course in their academics.
• Kotlin is also a suitable language for learning programming fundamentals and competitive programming.
• Writing code with Kotlin might feel like it is a scripting language, but it is a statically typed programming language.

Guys, this is my FIRST POST on DEV community, please support me by giving a like to this post, and feel free to share your feedback in comment section below.