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Hi there we know that platform independence is one of the key benefits of jello.

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But before understanding how jolly to use black comedy Burnetts we need to first understand what black

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from dependency is to understand back home dependency.

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We also need to know what abolitionists compulsion is a very fundamental concept in computer science

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.

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If you are new to programming or not completely sure about what compulsion is the short discussion on

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compilation should be helpful.

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Let's start with the absolute basic concepts of a computer.

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Every computer has a fixed set of instructions.

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The chip on the stunts on a computer program is made up off some of these instructions.

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That is the instructions help a computer program will form something meaningful.

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Each instruction is basically a sequence off zeroes and once that is an instruction has it binary format

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such instructions that computer understands.

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It's called machine language.

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That is the language which a machine understands machine language is also referred to as machine code

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and this sometimes also referred to as native code.

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And here's an example of machine instruction which does the program to do something.

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Not as you may imagine it would be an extremely difficult task for programmers to write programs in

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machine language which how only zeros and ones.

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So it's got to be simpler than this.

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So computer scientists came up with another language called assembly language which was much more easier

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to read and write.

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Here's an example to add to them first which for sure is much more explicit than machine code.

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So assembly language but a Whites Soden higher level rubescens horror writing instructions.

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But computers understand only machine language they don't understand assembly language so that is a

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program called assembler which translates assembly language instructions to machine language instructions

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which a computer can't understand.

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No but machine language on assembly language are referred to as low level languages.

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And that's because they use low level details of the computer.

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One example would be specifying the memory location where we are storing data and writing programs even

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in assembly language is still tedious supercop on most wanted programs to be expressed in a more easier

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and they also wanted to hide the low level details.

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So in time that came up with high level languages I'm some example high level languages in Fortran C

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C++.

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Our very own Java and C-Sharp and they use English like words mathematical notations and punctuations

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to write programs so that much easier to write and read as we will see in this course.

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And of course they also hide low level details of the computer.

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So could it be mostly use only high level programming languages.

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Assembly language is not used very much and is used only where performance is critical.

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Like in the case of operating systems or electronic devices and in terms of terminology.

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Sourcecode is a term that is used to refer to any code which is expressed in any programming language

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.

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Not like in the case of assembly language.

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Source code cannot also be understood by a computer.

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So we need to translate source code into machine language.

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The transmission from source code to machine code is done by a program called compiler machine code

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which is the executable program is then executed directly by CPQ in a separate step.

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Note that in this illustration we are calling the translator language as target language or not machine

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language.

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And that's because in some cases it may be something else too.

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For example in the case of C or C++ hardit language would be machine called Hollywood Angelas Yes it

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is Java bytecode which will be discussed later.

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Sometimes not a good language can also be another programming language.

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There are some code operations that a compiler performs on let's see what those are really fine syntax

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and semantics of the sourcecode is one of them.

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This ensures that the source code complies with the rules of the programming language.

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For example a program is made up of statements and in case of Java every statement must end with this

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inequality.

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Now if a statement doesn't end with a semicolon then the compiler detects it as a syntactic error unreported

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to the upper compiler also performs certain code optimizations for faster execution.

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Finally it generates machine code from the intermediate optimized core.

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A compiler is a pretty complex program and these core operations are basic operations that any compiler

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supports.

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As you will see in this course it Djala compiler performs tons of additional operations to ease the

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program much dusk so the completion process can be slow due to the complexity and translation.

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However once compiled machine code execution will be very fast on the machine code can be executed anytime

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on any number of things.

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Any change to the source code requires complete recompilation.

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Next we a look at platform dependency which will also give you an idea on how a C program is compiled

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on Windows.

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On Linux machines you're not going to write any code for this discussion but towards the end of the

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chapter we will write compile and execute our first Gela program.

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So in this chapter we will write only one program but as a cost progresses we will write lots and lots

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of programs on every concept that we learn will be demonstrated through them or grow grass.

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So that's about it.

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Thank you.

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Our next move will look at black from dependency