A4 PAPERS WORLD WIDE - AN OVERVIEW

The quality of A4 Paper is determined by GSM (gram per square meter). It's in reality the thickness in the paper. For instance an 80gsm paper are going to be thicker than 70gsm paper. Thicker papers are used for drawing with markers or coloured pencils of bigger cross-section.I am a Yemeni citizen (a third-world state which is at war and executes g