Advanced PowerBuilder

What are Objects?

They're nothing but software programming models. In your everyday life, you're surrounded by objects: cars, coffee machines, phones, fax machines, and so on. Similarly, software applications contain objects: buttons, spreadsheets, spreadsheet cells, property lists, menus, and so on. These objects have states and behaviors. You can represent these things with software constructs called objects, which can be defined by their state and their behavior.

Take your everyday transportation,  a car, it can be modeled by an object. A car has state ( how fast it's going, in which direction, its fuel consumption, and so on) and behavior ( starts, stops, turns, slides, and runs into trees ).

You drive your car to the office, where you keep track of your stock portfolio. In your daily interactions with the stock market, a stock can be modeled as an object. A stock has state ( daily high, daily low, open price, close price, earnings per share, relative strength ), and behavior ( changes value, performs splits, has dividends ).

After watching your stock tumble, you rush to the cafe to console yourself with a cup of hot coffee. The espresso machine can also be modeled as an object. It has state ( water temperature, amount of coffee in the hopper ) and it has behavior ( emits steam, makes noise, and brews a perfect cup of coffee ).

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