what's the difference between flow chart and structure diagrams and pseudo code
Yes
compiler
Coverts source code into object code
Pseudo code cannot be processed by a machine, it is solely intended for processing by humans.
It coverts your source code into machine code so the computer can execute it.
Source code is the human-readable version of a program written in a programming language, while object code is the machine-readable version generated by a compiler from the source code. The "best" between them depends on the context: source code is easier for humans to read and modify, while object code is necessary for a computer to execute the program. Both are important in software development.
It doesn't. Pseudo code isn't a programming language, it is just there to give an idea of how you could write a program.
the difference between that two words is the spelling, numbers of letters and the first letter in that two particular words
No, they are two different things, source code is human-readable and machine code is machine-readable (though it can be represented in assembly)
Source code is code written in a programming language, such as C++ or Java. It is designed to be architecture-independent and human-readable. Source code must be converted to object code (aka machine code) before it can be executed. Object code is architecture-dependent and is not easily human-readable (think ones and zeros). The point of this setup is that you can ensure that code you write in a programming language (source code) can be executed on ANY architecture that has a proper compiler.
No. There is no "right way" and "wrong way" of writing pseudo code, let alone qualifying with "absolute". However, a pseudo code is "wrong" if it cannot be understood, or it is incorrect in semantic (what the code tries to describe, solve, etc)