This is the 7477th most frequent Spanish word.
ing
The term "ing" is not a Spanish word. In English, it is a suffix used to form present participles and gerunds.
'Estudiando' is the gerund form ('-ing' equivalent in Spanish), used here to indicate a continuous action in progress.
Estoy estudiando para el examen mañana.
I am studying for the exam tomorrow.
'Viendo' is the gerund form ('-ing' equivalent in Spanish), used as a verbal action describing a simultaneous activity.
Viendo una película me relajé mucho.
Watching a movie, I relaxed a lot.
'Cantando' is the gerund form ('-ing' equivalent in Spanish), showing the manner or means in which the action (arrival) happened.