Introduction to Software Testing

History ...

• Fast forward to 1800: Watt’s patent expires.
• Now anyone is free to make high-pressure steam engines (HPSEs)!
• Two designs appear (one US, one UK)
• No separate condenser; instead, steam is used to push pistons directly.

History ...

• First widespread use of HPSEs is steamboats.
• It’s highly successful!
• Cheap, efficient.
• Makes transportation more affordable to the masses.
• Steamboat companies make money too; helps the growing economy.

History ...

• BOOM!
• Oh yeah, HPSEs tend to explode too.
• Steamboat passengers and crew blown up, scalded to death, drowned, impaled by hot iron, ...
• HPSEs also used in manufacturing industry. Guess what happens?

So what’s the problem?

• Well, HPS is dangerous stuff, but also:
• low standards of workmanship
• use of cheap, inferior materials
• poorly trained workers
• poorly trained operators
• bad quality control