Hosts
Mainframe:
- Services a large network
- Data processing and communications
- Emphasis on online real-time data processing and large scale data storage
Minicomputer:
- Originally architecturally different from mainframes
- Department -level data processing
- Often for specific tasks such as office automation, financial
- reporting etc.
- often specific technologies (e.g., IBM AS/400)
- Today minicomputers are being replaced by microcomputers
Microcomputer:
- Based on microprocessor technology
- used in local area networks as servers (e.g., file server, communications server, security server, electronic mail server)