KParts is the name of the component framework for the KDE desktop environment. An individual component is called a KPart. KParts are analogous to Bonobo components in GNOME, both of which are based on the same concepts as Microsoft's Object Linking and Embedding.
Konsole is available as a KPart and is used in applications like Konqueror and Kate. Good examples about how KParts can be used are Konqueror, which (among other things) uses the KWord part to display documents, KMPlayer part to play multimedia, and Kontact, which embeds kdepim applications under one roof.