Introduction To PYTHON , FEATURES, Python vs JAVA, Advantages, Applications

 Introduction To PYTHON

Python is a widely used general-purpose, high level programming language. It was created by Guido van Rossum in 1991 and further developed by the Python Software Foundation. It was designed with an emphasis on code readability, and its syntax allows programmers to express their concepts in fewer lines of code.

Python is a programming language that lets you work quickly and integrate systems more efficiently.

Writing our first program:

Just type in the following code after you start the interpreter.

# Script Begins    print("UJJWAL")    # Scripts Ends

Output:

UJJWAL

Let’s analyze the script line by line.
Line 1: [# Script Begins] In Python, comments begin with a #. This statement is ignored by the interpreter and serves as documentation for our code.
Line 2: [print(“UJJWAL”)] To print something on the console, print() function is used. This function also adds a newline after our message is printed(unlike in C). Note that in Python 2, “print” is not a function but a keyword and therefore can be used without parentheses. However, in Python 3, it is a function and must be invoked with parentheses.
Line 3: [# Script Ends] This is just another comment like in Line 1.
Python designed by Guido van Rossum at CWI has become a widely used general-purpose, high-level programming language.
Prerequisites:
Knowledge of any programming language can be a plus.
Reason for increasing popularity
Emphasis on code readability, shorter codes, ease of writing
Programmers can express logical concepts in fewer lines of code in comparison to languages such as C++ or Java.
Python supports multiple programming paradigms, like object-oriented, imperative and functional programming or procedural.
There exists inbuilt functions for almost all of the frequently used concepts.
Philosophy is “Simplicity is the best”.
LANGUAGE FEATURES
Interpreted
There are no separate compilation and execution steps like C and C++.
Directly run the program from the source code.
Internally, Python converts the source code into an intermediate form called bytecodes which is then translated into native language of specific computer to run it.
No need to worry about linking and loading with libraries, etc.
Platform Independent
Python programs can be developed and executed on multiple operating system platforms.
Python can be used on Linux, Windows, Macintosh, Solaris and many more.
Free and Open Source; Redistributable
High-level Language
In Python, no need to take care about low-level details such as managing the memory used by the program.
Simple
Closer to English language;Easy to Learn
More emphasis on the solution to the problem rather than the syntax
Embeddable
Python can be used within C/C++ program to give scripting capabilities for the program’s users.
Robust:
Exceptional handling features
Memory management techniques in built
Rich Library Support
The Python Standard Library is very vast.
Known as the “batteries included” philosophy of Python ;It can help do various things involving regular expressions, documentation generation, unit testing, threading, databases, web browsers, CGI, email, XML, HTML, WAV files, cryptography, GUI and many more.
Besides the standard library, there are various other high-quality libraries such as the Python Imaging Library which is an amazingly simple image manipulation library.
Python vs JAVA
Python
Java
Dynamically Typed 
No need to declare anything. An assignment statement binds a name to an object, and the object can be of any type.
No type casting is  required when using container objects
Statically Typed
All variable names (along with their types) must be explicitly declared. Attempting to assign an object of the wrong type to a variable name triggers a type exception.
Type casting is required when using container objects.
Concise Express much in limited words
Verbose Contains more words
Compact
Less Compact
Uses Indentation for structuring code
Uses braces for structuring code
Advantages : 
Presence of third-party modules 
Extensive support libraries(NumPy for numerical calculations, Pandas for data analytics etc) 
Open source and community development 
Versatile, Easy to read, learn and write
User-friendly data structures 
High-level language 
Dynamically typed language(No need to mention data type based on the value assigned, it takes data type) 
Object-oriented language 
Portable and Interactive
Ideal for prototypes – provide more functionality with less coding
Highly Efficient(Python’s clean object-oriented design provides enhanced process control, and the language is equipped with excellent text processing and integration capabilities, as well as its own unit testing framework, which makes it more efficient.)
(IoT)Internet of Things Opportunities
Interpreted Language
Portable across Operating systems 
 
Applications : 
GUI based desktop applications
Graphic design, image processing applications, Games, and Scientific/ computational Applications
Web frameworks and applications 
 Enterprise and Business applications 
 Operating Systems 
Education
Database Access
Language Development 
 Prototyping 
Software Development
 
Organizations using Python : 
Google(Components of Google spider and Search Engine) 
Yahoo(Maps) 
YouTube 
Mozilla 
Dropbox 
Microsoft 
Cisco 
Spotify 
Quora