Original: A ballpoint pen (also eponymously known in British English and Australian English as a biro and  bye-roe in Britain and Australia but sometimes  bee-roh" elsewhere, named after its credited, though contested, inventor László Bíró), is a modern writing instrument.
Simplified: A ballpoint pen (also called a biro - pronounced "BY-roe" - in British English after its inventor László Bíró), is a modern kind of pen for writing.