Out algorithms must be written in a programming language. A programming language has precise syntax (grammar) and semantics (meaning). An algorithm in a programming language is called a program. To be used by the machine it must be translated into a native language specific to the computer"s cpu (central processing unit) called machine language this translation is done by a compiler. A successfully compiled program only tells you if the programs syntax is correct, not it"s semantics. #include using namespace std; int main () return 0; Identifiers x , y - basically the variable. Declaration - set up containers for storage. Expression - change and exchange data form : expression; Expressions consist of operators, literals and identifiers. Literals are direct representations of data such as 2. 4, 5, or 1. 0e-5 identifiers are names given to data objects in declarations, in the previous program x and y were identifiers. These include +(add), * (multiply) , = (assign) , plus many others.