Syndeton or syndetic coordination in grammar is a form of syntactic coordination of the elements of a sentence (conjuncts) with the help of a coordinating conjunction.
In a simple syndeton, two conjuncts are joined by a conjunction: "I will have eggs and ham". This is a figure of speech.
In syndetic coordination with more than two conjuncts, the conjunction is placed between the two last conjuncts: "I will need bread, cheese and ham". The serial comma is not usually used in front of the conjunction between the last two items in British English, while American English generally suggests a comma: "I will need bread, cheese, and ham".