The term 'Common Interest' can be broken down into two words, BLOC and TIE. BLOC is a four letter word meaning a group of people or countries with a shared political or economic interest. TIE is a three letter word meaning a relationship between two or more people or groups that share a common interest. Common Interest is the idea that two or more people or groups have something in common that binds them together. This could be a shared hobby, profession, or even a shared goal. Common Interests are often used to bring people together and foster collaboration.