1. A computer implemented method comprising: processing, by one or more computers, a first indicium of a plurality of indicia applied by a user over a first portion of words in a document; determining, by the one or more computers, a first voice model to associate with the first portion of words, with the first voice model represented by the first indicium applied by the user over the first portion of words; and generating, by the one or more computers, an audible output corresponding to the words in the first portion of words using the voice model associated with the first portion of words.