These machines caused a stir in the industry with their compact dark grey cases, built-in trackball, and the innovative positioning of the keyboard that left room for palmrests on either side of the pointing device.

Portable PC computers at the time were still oriented toward DOS, and tended to have the keyboard forward towards the user, with empty space behind it that was often used for function key reference cards.

In the early days of Microsoft Windows, many notebook computers came with a clip on trackball that fit on the edge of the keyboard molding.

As usage of DOS gave way to the graphical user interface, the PowerBook's arrangement became the standard layout all future notebooks would follow.

Unlike the Macintosh Portable, however, which was essentially a battery-powered desktop in weight and size, the light colors and decorative recessed lines did not seem appropriate for the scaled-down designs.

[citation needed] When attempting to increase processing power, Apple was hampered by the overheating problems of the 68040; this resulted in the 100-series PowerBook being stuck with the aging 68030, which could not compete with newer-generation Intel 80486-based PC laptops introduced in 1994.

In 1994, the last true member of the 100-series form factor introduced was the PowerBook 150, targeted at value-minded consumers and students.

The Duos were a series of very thin and lightweight laptops with a minimum of features, which could be inserted into a docking station to provide the system with extra video memory, storage space, connectors, and could be connected to a monitor.

The PowerBook 500 series was released as Apple was already moving its desktop machines to the PowerPC processor range, and a future upgrade was promised from the start.

At the same time Newer Technology offered an Apple-authorized 117 MHz Motherboard, which was more popular than the Apple product, and optionally came without any RAM.

Nonetheless, the internal architecture of the 500 series meant that the speed increase provided by the 100 and 117 MHz upgrades was, for most users, relatively small.

In its 5300ce incarnation with a TFT of 800×600 pixels, Apple offered a 117 MHz PPC, 32 MB of onboard RAM, and a hot-swappable drive bay.

After Apple offered an Extended Repair Program, the series turned into a remarkably attractive machine, but never lost its bad reputation.

[4] Debuting at roughly the same time as the G3 iMac, the "WallStreet/Mainstreet" series composed of models with varying features, such as different processing speeds (from 233 to 300 MHz) and the choice of 12-, 13-, or 14-inch screens.

A second PowerBook G3 Series code-named "PDQ" was introduced later in 1998, with minor changes in configuration options, notably the inclusion of L2 cache in even the lowest-priced 233 MHz model, which helped overall performance.

The result, introduced in January 2001, was a completely re-designed New World PowerBook with a titanium skin and a 15.2-inch wide-aspect screen suitable for watching widescreen movies.

[7] Because of their large screens and high performance, Titanium Powerbooks were the first laptops to be widely deployed as desktop replacement computers.

Both machines were made of anodized aluminum (coining the new nickname AlBook), featured DVD-burning capabilities, AirPort Extreme networking, Bluetooth, and 12.1-inch or 17-inch LCD displays.

Memory and hard drive defaults were increased to 512 MB and 5400 rpm, respectively, with a new storage maximum of 100 GB on the 17-inch model.

Each model also received an enhanced trackpad with scrolling capabilities, a revised Bluetooth module supporting BT 2.0+EDR, and a new feature that parks the drive heads when sudden motion is detected by an internal sensor.

The joint Apple/CPSC press release stated that an internal short could cause the battery cells to overheat, posing a fire hazard.

[10] About 1.1 million battery packs in the United States were recalled; an additional 700,000 were sold outside the U.S. At the 2006 Macworld Conference & Expo, the MacBook Pro was introduced.