Computing is becoming increasingly mobile, requiring applications and services to adapt to changing contexts in dynamic environments. An ontology-based context model represents, manipulates, and accesses context information to provide a common vocabulary for sharing semantic context between users, devices, and services. The proposed context ontology defines basic concepts like person, location, computational entity, and activity, and their properties and relationships, using OWL. It aims to support context-aware tasks in a middleware framework. The software requirements include J2ME, a wireless toolkit, Tomcat, MySQL, and ontology editors, and the hardware includes a PC and WAP-enabled mobile.