Dashboard is a second screen/desktop of a Macbook that allows to add widgets, like Clock, Currency Converter, Dictionary, translator etc.. It existed in Mac since 2005 when OS X Tiger was launched, and it still exists. It has not ben permanently removed but disabled by default in OS X EL Capitan.
Those who are using OS X EL Capitan Beta 7 informed that Dashboard is not available by default any more. However, you still have the option to enable it. It can be enabled accessing System Preferences –> Mission Control and choose “As Space” from the Dashboard drop down-menu. Once enabled, you can press the Dashboard Key to make use of it.
OS X Dashboard has not received any major update for years, but there are still people who use it. This was a wise decision that Apple left the chance to enable as per users’ requirement. OS X EL Capitan is still in beta mode, and Apple may be just testing what needs to be done. However, the final release may have something different.
OS X EL Capitan will be launched this fall that will bring great improvement in Mac performance. We would also be able to use two apps at the same side-by-side in full screen.