The Hewlett-Packard Company (NYSE: HPQ), commonly known as HP, is currently the world's largest information technology corporation (by revenue) and is known worldwide for its printers, personal computers and related services. Headquartered in Palo Alto, California, United States, it has a global presence in the fields of computing, printing, and digital imaging, and also provides software and services. The company, which once catered primarily to engineering and medical markets—a line of business it spun off as Agilent Technologies in 1999—now markets to households and small business products such as printers, cameras and ink cartridges found in grocery and department stores.

HP posted US$91.7 billion in annual revenue in 2006 compared to US$91.4 for IBM, making it the world's largest technology vendor in terms of sales. HP is now the No. 1 ranking company in worldwide personal computer shipments, surpassing rival Dell, market research firms Gartner and IDC reported in October 2006;  the gap between HP and Dell widened substantially at the end of 2006, with HP taking a near 3.5% market share lead.

The company released an outlook for FY07 of between $100.5 and $100.9 billion during it's Q2 earnings results.

Bill Hewlett and Dave Packard both graduated from Stanford University in 1934. The company originated in a garage in nearby Palo Alto while they were post-grad students at Stanford during the Great Depression. The partnership was formalised on January 1, 1939 with an investment of US$538.[4] Bill Hewlett and Dave Packard tossed a coin to decide whether the company they founded would be called Hewlett-Packard or Packard-Hewlett. Dave won the coin toss but named their electronics manufacturing enterprise the "Hewlett-Packard Company."

HP incorporated on August 8, 1947, and went public on November 6, 1957.

Of the many projects they worked on, their first financially successful product was a precision audio oscillator, the Model 200A. Their innovation was the use of a small light bulb as a temperature dependent resistor in a critical portion of the circuit. This allowed them to sell the Model 200A for $54.40 when competitors were selling less stable oscillators for over $200. The Model 200 series of generators continued until at least 1972 as the 200AB, still tube-based but improved in design through the years. At 33 years, it was perhaps the longest-selling basic electronic design of all time.

One of the company's earliest customers was The Walt Disney Company, who bought eight Model 200B oscillators (at $71.50 each) for use in certifying the Fantasound surround sound systems installed in theaters for the movie Fantasia.

The company was originally rather unfocused, working on a wide range of electronic products for industry and even agriculture. Eventually they elected to focus on high-quality electronic test and measurement equipment. Throughout the 1940s to well into the 1990s the company focused on making signal generators, voltmeters, oscilloscopes, counters, and other test equipment. Their distinguishing feature was pushing the limits of measurement range and accuracy. For instance, almost every HP voltmeter or signal generator has one or more extra clicks of its knobs than its competitors. HP volt- or ammeters would measure down and up an extra 10 to 100 times the units of other meters. Although there were good reasons why competing meters stopped at 1 volt full scale, HP engineers figured out ways of extending the range of their equipment by a considerable amount. They also focused on extreme accuracy and stability, leading to a wide range of very accurate, precise, and stable frequency counters, voltmeters, thermometers, and time standards.

HP is recognized as the symbolic founder of Silicon Valley, although it did not actively investigate semiconductor devices until a few years after the "Traitorous Eight" had abandoned William Shockley to create Fairchild Semiconductor in 1957. Hewlett-Packard's HP Associates division, established around 1960, developed semiconductor devices primarily for internal use. Instruments and calculators were some of the products using these devices.

HP experimented with using Digital Equipment Corporation minicomputers with its instruments. But after deciding that it would be easier to buy another small design team than deal with DEC, HP entered the computer market in 1966 with the HP 2100 / HP 1000 series of minicomputers. A simple accumulator-based design, with registers arranged somewhat similarly to the Intel x86 architecture still used today, it would last 20 years and several attempts to replace it. It would give birth to the HP 9800 and HP 250 series of desktop and business computers, which predated the PCs by nearly a decade. The HP 3000 was an advanced stack based design for business computing server later redesigned with RISC technology that has only recently been retired from the market. The HP 2640 series of smart and intelligent terminals introduced forms-based interfaces to ASCII terminals, and screen labeled function keys now commonly used on gas pumps and bank ATMs. Although scoffed at in the formative days of computing, HP would eventually surpass even IBM as the world's largest technology vendor in sales.

HP is acknowledged by Wired magazine as the producer of the world's first personal computer, in 1968, the Hewlett-Packard 9100A.[5] HP called it a desktop calculator because, as Bill Hewlett said, "If we had called it a computer, it would have been rejected by our customers' computer gurus because it didn't look like an IBM. We therefore decided to call it a calculator, and all such nonsense disappeared." An engineering triumph at the time, the logic circuit was produced without any integrated circuits; the assembly of the CPU having been entirely executed in discrete components. With CRT readout, magnetic card storage, and printer the price was around $5000.

The company earned global respect for a variety of products. They introduced the world's first handheld scientific electronic calculator in 1972 (the HP-35), the first handheld programmable in 1974 (the HP-65), the first alphanumeric, programmable, expandable in 1979 (the HP-41C), and the first symbolic and graphing calculator HP-28C. Like their scientific and business calculators, their oscilloscopes, logic analyzers, and other measurement instruments have a reputation for sturdiness and usability (the latter products are now part of spin-off Agilent's product line). The company's design philosophy in this period was summarized as "design for the guy at the next bench".

In 1984, HP introduced both inkjet and laser printers for the desktop. Along with its scanner product line, these have later been developed into successful multifunction products, the most significant being single-unit printer/scanner/copier/fax machines. The print mechanisms in HP's tremendously popular LaserJet line of laser printers depend almost entirely on Canon's components (print engines), which in turn use technology developed by Xerox. HP develops the hardware, firmware, and software that convert data into dots for the mechanism to print.

In the 1990s, HP expanded their computer product line, which initially had been targeted at university, research, and business customers, to reach consumers. Later in the decade HP opened hpshopping.com as an independent subsidiary to sell online, direct to consumers; the store was rebranded "HP Home & Home Office Store" in 2005. HP also grew through acquisitions, buying Apollo Computer in 1989, Convex Computer in 1995, and Compaq in 2002. Compaq itself had bought Tandem Computers in 1997 (which had been started by ex-HP employees), and Digital Equipment Corporation in 1998. Following this strategy HP became a major player in desktops, laptops, and servers for many different markets.

In 1987, the Palo Alto garage where Hewlett and Packard started their business was designated as a California State historical landmark.

In 1999, all of the businesses not related to computers, storage, and imaging were spun off from HP to form Agilent. Agilent's spin-off was the largest initial public offering in the history of Silicon Valley. The spin-off created an $8 billion company with about 30,000 employees, manufacturing scientific instruments, semiconductors, optical networking devices, and electronic test equipment for telecom and wireless R&D and production. Also in July 1999, HP appointed Carly Fiorina as CEO. Fiorina was the first woman ever to serve as CEO of a company included in the Dow Jones Industrial Average. Fiorina was forced to resign on February 9, 2005.