2.4 Capabilities of Software

1. 2.4 Capabilities of Software • Describe the desirable features of applications: • Portability • Upgrade paths • Reliability • Understand the criteria for selecting an application • Know how to evaluate software

2. Portability Why is there a need for portability of data? • Users of different hardware, operating systems, applications, or even different versions of the same application may need to share data • This is especially important in a networked environment • For example, students in the first school at which I taught used Windows PCs, Acorn RISC-PCs and Network Computers (NCs) all on the same network

3. Portability What are the barriers to the portability of data? • Too many competing file formats – e.g. for an image you have bmp, GIF, jpeg, PNG, etc. • Manufacturers protecting their market share – Lotus doesn’t want you to open 1-2-3 files in Excel • Manufacturers deviating from (or “extending”) standards, e.g. Microsoft with HTML and Java • Differences between operating systems – e.g. fonts, UI standards, peripheral support, etc.

4. Portability What can we do to improve portability? • Introduce standards – e.g. the new open document standard for word processors • Use filters to convert between file formats – e.g. you can use filters to open Works files in Word • Use more portable formats such as .csv or RTF – although you will sometimes lose formatting or features • You can copy and paste data between applications (but only on the same machine)