low - high level languages

instruction set

the complete set of all the instructions in machines code and chip level that a computer can understand and process. it is individual to each chip

machine code

code written in binary that the computer or microprocessor can directly understand and process

assembly code

code that us written in mnemonics. one mnemonic represents one instruction in machine code. it is low level but has to be translated into machine code using an assembler.

compiler

translates the code as a whole unit, into one new executable file of optimized source code and a report of all the errors found. one single high level language ends up as several machine code instructions

benefits of compilers

produces fast, executable code that runs directly on processor
no need for translation software on the machine where code will be executed - code is platform independent
source code cannot be modified and is not accessible

compiler cons

more difficult to debug as one error can produce lots of spinoff errors

comments/source code are not visible once compiled

future changes require code to be recompiled

interpreter

source code is translated one line at a time into machine code and directly executed. Execution stops as soon as an error is identified.

interpreter pros

interpreting makes it easier to debug code as errors are displayed as soon as they are found

interpreter cons

speed of execution of program loops is slower as each line has to be interpreted individually every time it is run. it cannot be ran without an interpreter.

compiler uses in industry

used to distribute a file which can be run without the compiler, so users dont have to buy or download one

interpreter uses in industry

used for programme development as line by line error correction means errors can be corrected immediately

assemblers

the whole assembly code is translated into a new executable machine code file. This means the file can be run on a device without an assembler

assmblers in industry

used when a programmer needs to directly access specialist hardware, such as in an embedded system

byte code

intermediate versions of the programs you write, which partly compiles/prepares programs for actual execution. achieves platform independence

platform independence

you can operate in the same way no matter which machines you are running. the program can be run on any machines.