Abstract
This study examines the direction and scape of comprehension-related activities of professional programmers carrying out several comprehension and maintenance activities over time. Procedural and abject-oriented (OO) programmers studied a program and subsequently performed modifications during two sessions. Results showed that the OO programmers tended to use a strongly top-down approach to program understanding during an early phase of study of the program but increasingly used a bottom-up approach during the maintenance tasks. The procedural programmers used a more bottom-up orientation throughout all activities. The scape of the activities was greater for the procedural than for the OO programmers. However, regardless of paradigm, the programmers over time built a broad, rather than a localized, view of the program.