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As a concrete example of a classic screen scraper, consider a hypothetical legacy system dating from the 1960s—the dawn of computerized [[data processing]]. Computer to [[user interface]]s from that era were often simply text-based [[dumb terminal]]s which were not much more than virtual [[teleprinter]]s (such systems are still in use {{As of|2007|alt=today}}, for various reasons). The desire to interface such a system to more modern systems is common. A [[Robustness (computer science)|robust]] solution will often require things no longer available, such as [[source code]], system [[documentation]], [[Application programming interface|API]]s, or [[programmers]] with experience in a 50-year-old computer system. In such cases, the only feasible solution may be to write a screen scraper that "pretends" to be a user at a terminal. The screen scraper might connect to the legacy system via [[Telnet]], [[emulator|emulate]] the keystrokes needed to navigate the old user interface, process the resulting display output, extract the desired data, and pass it on to the modern system. A sophisticated and resilient implementation of this kind, built on a platform providing the governance and control required by a major enterprise—e.g. change control, security, user management, data protection, operational audit, load balancing, and queue management, etc.—could be said to be an example of [[robotic process automation]] software, called RPA or RPAAI for self-guided RPA 2.0 based on [[artificial intelligence]].
In the 1980s, financial data providers such as [[Reuters]], [[Dow Jones & Company|Telerate]], and [[Quotron]] displayed data in 24×80 format intended for a human reader. Users of this data, particularly [[Investment banking|investment banks]], wrote applications to capture and convert this character data as numeric data for inclusion into calculations for trading decisions without [[data entry clerk|re-keying]] the data. The common term for this practice, especially in the [[United Kingdom]], was ''page shredding'', since the results could be imagined to have passed through a [[paper shredder]]. Internally Reuters used the term 'logicized' for this conversion process, running a sophisticated computer system on [[
More modern screen scraping techniques include capturing the bitmap data from the screen and running it through an [[Optical character recognition|OCR]] engine, or for some specialised automated testing systems, matching the screen's bitmap data against expected results.<ref>{{Cite journal|url = http://groups.csail.mit.edu/uid/projects/sikuli/sikuli-uist2009.pdf|title = Sikuli: Using GUI Screenshots for Search and Automation|last = Yeh|first = Tom|date = 2009|journal = UIST}}</ref> This can be combined in the case of [[GUI]] applications, with querying the graphical controls by programmatically obtaining references to their underlying [[Object-oriented programming|programming objects]]. A sequence of screens is automatically captured and converted into a database.
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