History of Android

 The Android is a Linux Based Operating System by GOOGLE which provide a rich application Framework and help in developing interactive applications. The OS first OS version was introduced in 2007 with many of its versions named in Alphabetical order ranging from A-N and upcoming is O. 

DETAILED ABOUT ANDROID VERSIONS 

◆ Alpha – In this( Android 1.0) was the first versions of Android operating System by Google. It has basic functionality with a simple browser and other Google apps like Gmail, Maps and YouTube.

◆ Beta –   Later on with Android 1.1 few more functionality added, the API changes from Level 1 in Android 1.0 to Level 2. It supports attachment with MMS.

◆ Cupcake – Cupcake was Android second version with new features as well as the Android framework API updated. It was Android 1.5 with on Screen Keyboard , Bluetooth and Updated UI for applications.

◆ Donut – It was Android 1.6 nicknamed as DONUT. It added support for CDMA , additional screen sizes, talk to speech engine and battery indicator.

◆ Éclair – Android 2.0-2.1 as like other versions this also come up with a nickname as ECLAIR and lot more functions & features. It come up with Bluetooth 2.1 , live wallpaper, HTML 5 support, ability to search SMS & mms, flash support, digital zoom and more camera features

◆Froyo – Android version 2.2-2.2.3 introduced with USB tethering & Wi-Fi hotspot functionality and apps can now be installed on memory card. Support Adobe flash, increased speed and performance of applications with new features.

◆ Gingerbread – Gingerbread (Android 2.3-2.3.7) introduced with updated User Interface which provide more ease to use. Features are like sensors, multiple cameras(Front & back), virtual keyboard, better text suggestion, voice input capability and press hold copy paste capability.

◆ Honeycomb – This Android platform Honeycomb was designed for large screens like tablets so interface elements like virtual keyboard optimized for bigger screen. Home screen is optimized, tabs are introduced in browser with additional incognito mode and video chat & Gtalk is supported.

◆ Ice Cream Sandwich –Ice Cream sandwich come in 2011 bringing all new look. It gives more ease to user like user can quickly swipe to close the apps, new gallery layout and built in photo editor.

◆ Jelly Bean – Google made Operating System more responsive with Jelly Bean and introduces file sharing with Android Beam. Restricted profile, Dial Pad complete, supported other languages like Hindi, changed

What is Java 

Java is an object-oriented programming language developed by Sun Microsystems, a company 

best known for its high-end Unix workstations. Modeled after C++, the Java language was

designed to be small, simple, and portable across platforms and operating systems, both at the

source and at the binary level (more about this later).

Java is often mentioned in the same breath as HotJava, a World Wide Web browser from Sun

like Netscape or Mosaic What makes HotJava different from most other

browsers is that, in addition to all its basic Web features, it can also download and play applets

on the reader’s system. Applets appear in a Web page much in the same way as images do, but

unlike images, applets are dynamic and interactive. Applets can be used to create animations,

figures, or areas that can respond to input from the reader, games, or other interactive effects on

the same Web pages among the text and graphics.

Although HotJava was the first World Wide Web browser to be able to play Java applets, Java

support is rapidly becoming available in other browsers. Netscape 2.0 provides support for Java

applets, and other browser developers have also announced support for Java in forthcoming

products.

  To create an applet, you write it in the Java language, compile it using a Java compiler, and refer

to that applet in your HTML Web pages. You put the resulting HTML and Java files on a Web

site much in the same way that you make ordinary HTML and image files available. Then, when

someone using the HotJava browser (or other Java-aware browser) views your page with the

embedded applet, that browser downloads the applet to the local system and executes it, and

then the reader can view and interact with your applet in all its glory (readers using other

browsers won’t see anything). You’ll learn more about how applets, browsers, and the World

Wide Web work together further on in this book.

The important thing to understand about Java is that you can do so much more with it besides

create applets. Java was written as a full-fledged programming language in which you can

accomplish the same sorts of tasks and solve the same sorts of problems that you can in other

programming languages, such as C or C++. HotJava itself, including all the networking, display,

and user interface elements, is written in Java.

     Why Learn Java?

 At the moment, probably the most compelling reason to learn Java—and probably the reason

you bought this book—is that HotJava applets are written in Java. Even if that were not the case,

Java as a language has significant advantages over other languages and other programming

environments that make it suitable for just about any programming task. This section describes

some of those advantages.

                                                    Java Is Easy to Learn

In addition to its portability and object-orientation, one of Java’s initial design goals was to be

small and simple, and therefore easier to write, easier to compile, easier to debug, and, best of

all, easy to learn. Keeping the language small also makes it more robust because there are fewer

chances for programmers to make difficult-to-find mistakes. Despite its size and simple design,

however, Java still has a great deal of power and flexibility Java is modeled after C and C++, and much of the syntax and object-oriented structure is

borrowed from the latter. If you are familiar with C++, learning Java will be particularly easy for

you, because you have most of the foundation already.

Although Java looks similar to C and C++, most of the more complex parts of those languages

have been excluded from Java, making the language simpler without sacrificing much of its

power. There are no pointers in Java, nor is there pointer arithmetic. Strings and arrays are real

objects in Java. Memory management is automatic. To an experienced programmer, these

omissions may be difficult to get used to, but to beginners or programmers who have worked

in other languages, they make the Java language far easier to learn.

What is Kotlin

according to Wikipedia Kotlin a cross-platform, statically typed, general-purpose programming language with type inference. Kotlin is designed to interoperate fully with Java, and the JVM version of Kotlin's standard library depends on the Java Class Library, but type inference allows its syntax to be more concise. Kotlin mainly targets the JVM, but also compiles to JavaScript (for e.g. frontend web applications using React or native code (via LLVM), e.g. for native iOS apps sharing business logic with Android apps. Language development costs are borne by JetBrains, while the Kotlin Foundation protects the Kotlin trademark.

On 7 May 2019, Google announced that the Kotlin programming language is now its preferred language for Android app developers. Since the release of Android Studio 3.0 in October 2017, Kotlin has been included as an alternative to the standard Java compiler. The Android Kotlin compiler targets Java 6 by default, but lets the programmer choose to target Java 8 up to 13, for optimization, or more features.