In the world of politics, and democracy, media outlets, researchers and others are trying to figure out how a poltical actor, party or candidate, will do in an election. This is a very important factor as a poll indicates who will get what amount of the votes and will be able to some level predict what the outcome will be. It is a way for non-politcal actors to evaluate the election process and to see that it is done under right circumstances, while it is also something of a scientific measure to be able to predict the future and understand politics.
In the world, some sources are big and represent world knowledge to a high extent. But there is no real world polling place to get to see the polling of all elections in the world. One actor that polls opinions in the world is for example Gallup. It is are a global analytics and advice firm that want to assist leaders and organisations. They have more than 80 years experience of data collection and 99% of the world´s population is represented by their world poll. There are 160 countries with data in their Gallup Analytics database. But looking into political elections, national media news outlets in respective country is a better source.
Polling can work different from country to country and state to state within countries. The world awaits for example who will be the next president of the USA and Real Clear Politics is following different polls which summarises the opinions of the american people on who they would like to see as the contender to Donald Trump in the general election in 2020. In the same way, countries collect their own polling data and that is often found in a countries media outlet. They report on pollings being done from various polling actors ahead of elections. The polling might be very advanced in some countries, while it is simpler in others.