You can find a list of worldwide stock exchanges on this website, together with the stock market symbols (Market Identification Codes - MIC).
Almost every data provider or broker uses different stock market symbols today, even though an International Standard (ISO 10383) specifies a universal method of identifying exchanges, trading platforms and regulated or non-regulated markets as sources of prices and related information in order to facilitate automated processing.
On this site, you can find a list of worldwide stock exchanges along with MIC stock market symbols. Direct links to official exchanges websites are also available behind the Institution Description column. If you are looking for more information about structural changes in global stock markets in last decade, please visit Stock Market Today website.