[ACM Press the 2007 annual research conference of the South African institute of computer scientists and information technologists - Port Elizabeth, South Africa (2007.10.02-2007.10.03)] Proceedings of the 2007 annual research conference of the South African institute of computer scientists and information technologists on IT research in developing countries - SAICSIT '07 - A comparative study of two usability evaluation methods using a web-based e-learning application