The Programming languages started with the low level language( 1's and zero's , so no conversion is needed.
Assembly language is used mnemonics ( ADD,INC,DEC) so needs conversions as the machine cannot understand it directly.
there comes the Assembler.
Now the question is how the Assember was implemented, i mean which language?
soon compilers came in to picture.
how they are written i mean using which language?
i read, c compiler was wirtten in C itself .
then how it was compiled.