Data Source API is used to create plug-ins receiving data. API is divided into two types. The first type is used to create the code responsible for collecting the data. Data can be in periodicities: millisecondly, secondly, minutely, hourly, daily, monthly and yearly. The second type, is used to create the GUI, with which the user can select data to download. Each such plug-in can use the default GUI in which the user must enter the unique symbol ID and select the data periodicity.