9. The method of claim 6 , wherein the task comprises at least one of: outputting content to the user; causing an action be performed by an application that is external to the system; or providing access to a web page.
6. A method comprising: causing a virtual assistant to carry out a conversation with a user, wherein the virtual assistant is configured with instructions stored in computerized memory to access features of a knowledge base stored in a computer readable media, the features organized to trigger outputs according to units of vocabulary patterns arranged in the features, wherein the vocabulary patterns are stored in the memory with respective labels and the instructions implement the following steps: receiving a speech input string via the virtual assistant during the conversation; substituting portions of the speech input string with sets of terms bearing corresponding labels that refer back to the respective labels of the knowledge base; converting the speech input string to converted data comprising the sets of terms; matching the respective labels and the corresponding labels to identify a digital response to the speech input; causing the digital response to be presented to the user in real-time via the virtual assistant; and causing a task to be performed at least in part by the virtual assistant.