Bravo (software)

Bravo (software). Bravo was a pioneering WYSIWYG word processing program developed at the Xerox PARC research facility in the 1970s. It was created for the Xerox Alto, one of the first personal computers, and introduced revolutionary concepts like on-screen formatting and the mouse-driven manipulation of text. The software's innovations directly influenced the development of modern document preparation systems and graphical user interfaces.

Overview

Developed by a team including Charles Simonyi and Butler Lampson, Bravo represented a fundamental shift from command-line text editors. It operated on the Xerox Alto, which was equipped with a bitmap display, a mouse, and an Ethernet connection. The program's most significant contribution was its implementation of a true WYSIWYG display, allowing users to see documents on screen exactly as they would appear when printed on a laser printer like the Xerox Star or later models. This approach contrasted sharply with the markup languages used by contemporary systems such as RUNOFF or TeX.

Features

Bravo introduced a suite of features that became standard in later word processors. It supported multiple fonts and sizes, text justification, and proportional spacing on the display. Users could interact with text through direct manipulation using the mouse for selecting, cutting, and pasting, a novel concept at the time. The software also incorporated advanced layout capabilities, enabling the creation of complex documents with embedded graphics. Its model of storing both the textual content and the formatting instructions together was a foundational idea for future software like Microsoft Word.

Development and history

The project began in the early 1970s at Xerox PARC, with key figures like Butler Lampson and Charles Simonyi leading the engineering effort. The development was closely tied to the creation of the Xerox Alto hardware and the Gypsy editor, which explored modeless interaction. After its internal use at Xerox PARC, the concepts evolved into the document system for the commercial Xerox Star office workstation. Charles Simonyi later joined Microsoft, where his experience with Bravo heavily influenced the design of Microsoft Word and other applications in the Microsoft Office suite, cementing the software's legacy in the history of computing.

Applications and use cases

Within Xerox PARC, Bravo was used extensively for preparing research papers, technical documentation, and internal memos, leveraging the facility's Ethernet network and laser printer infrastructure. Its principles were applied to the Xerox Star, aiming to create an integrated office automation system. The underlying paradigms of direct manipulation and visual feedback pioneered by Bravo became essential to later GUI-based programs on systems like the Apple Macintosh and Microsoft Windows. The software's design philosophy also informed the development of early desktop publishing software such as Adobe PageMaker.

Technical specifications

Bravo was written for the Xerox Alto platform, which utilized a bitmap display with a resolution of 606 by 808 pixels. The program was implemented in the BCPL programming language and relied on the Alto's Mesa operating environment. It stored documents in a proprietary format that encapsulated both text and precise formatting metadata. This architecture required significant computational resources for the era, including the Alto's custom microprocessor and substantial memory, setting a precedent for the resource demands of future WYSIWYG applications on personal computers.

Category:Word processors Category:Xerox Category:1974 software