In 1901 Frank Hornby, a clerk from Liverpool, England, invented and patented a new toy called "Mechanics Made Easy" that was based on the principles of mechanical engineering. It was a model construction kit consisting of perforated metal strips, plates and girders, with wheels, pulleys, gears and axles for mechanisms and motion, and nuts and bolts to connect the pieces.

The perforations were at a standard ½ inch (12.7 mm) spacing, the axles were 8-gauge, and the nuts and bolts used 5/32 inch BSW threads. The only tools required to assemble models were a screwdriver and spanners (wrenches). It was more than just a toy: it was educational, teaching basic mechanical principles like levers and gearing.

The parts for Hornby's new construction kit were initially supplied by outside manufacturers, but as demand began to exceed supply, Hornby setup his own factory in Duke Street, Liverpool. As the construction kits gained in popularity they soon became known as Meccano and went on sale across the world.

In September 1907, Hornby registered the Meccano trade mark, and in May 1908, he formed Meccano Ltd. To keep pace with demand, a new Meccano factory was built in Binns Road, Liverpool in 1914, which became Meccano Ltd's headquarters for the next 60 years. Hornby also established Meccano factories in France, Spain and Argentina. The word "Meccano" was thought to have been derived from the phrase "Make and Know".

The first construction sets had parts that were rather crudely made: the metal strips and plates had a tinplate finish, were not rounded at the ends and were not very sturdy. But manufacturing methods were improving all the time and by 1907 the quality and appearance had improved considerably: the metal strips were now made of thicker steel with rounded ends and were nickel-plated, while the wheels and gears were machined from brass.

The first sets under the new Meccano name were numbered 1 to 6. In 1922 the No. 7 Meccano Outfit was introduced, which was the largest set of its day, and the most sought after because of its model building capabilities and prestige.

In 1926, to mark the 25th anniversary of his patent, Hornby introduced "Meccano in Colours" with the familiar red and green coloured Meccano pieces. Initially plates were a light red and items like the braced girders were a pea-green. However, the following year strips and girders were painted dark green, the plates Burgundy red, while the wheels and gears remained brass.

In 1934 the Meccano pieces changed colour again: the strips and girders became gold while the plates were changed to blue with gold criss-cross lines on them. This new colour scheme was only available in Great Britain until the end of the Second World War in 1945. The old red and green sets were still produced for the export market and were re-introduced in Great Britain after the war.

In 1934 the nine basic Meccano outfits (numbered 00 to 7) were replaced by eleven outfits, labelled 0, A to H, K and L, the old No. 7 Outfit becoming the L Outfit. This L Outfit is often regarded as the best of the largest Meccano outfits. In 1937 the alphabetical outfit series was replaced by a numeric series, 0 to 10, the L Outfit being replaced by the smaller No. 10 Outfit. Although reduced in size from the L Outfit, the No. 10 Outfit became Meccano's flagship set and remained relatively unchanged until it was discontinued a half-century later in 1992.

Accessory sets were retained, numbered 1A to 9A, that converted a set to the next in the series (for example, accessory set 6A would convert a No. 6 set to a No. 7 set). As had been the case from early days, Meccano Ltd would also supply individual Meccano parts to complement existing sets.

World War II interrupted the production of Meccano in England when the Binns Road factory converted to manufacturing for the war effort. The Korean War in 1950 also disrupted production due to a metal shortage and it was not until the mid-1950s that Meccano production returned to normal with new parts being added to all the sets.

In 1955 outfits 00 to 10 as well as conversion sets 00A to 9A were available. In 1961 a Mechanisms Outfit and a Gears Outfit were added to the range, and in 1962 outfit 00 was withdrawn.

In the early 1960s Meccano Ltd experienced financial problems and was purchased by Lines Bros Ltd (Tri-ang) in 1964. In an attempt to redefine Meccano's image, the colour scheme was changed again, this time to yellow and black plates, with silver strips and girders. The silver was soon replaced by zinc in 1967 when it was found that the silver pieces marked easily.

The colours of yellow and black were chosen because they were the colours typically used by most large construction vehicles of the day. In 1970 electronic parts were introduced for the first time and the current black coloured plates were changed to blue. The range of sets was reduced by one with the deletion of the old No. 9 set and the renumbering of the old No. 0 to 8 sets to No. 1 to 9. The No. 10 set remained unchanged.

Lines Brothers went into voluntary liquidation in 1971 and Airfix Industries purchased Meccano Ltd in 1972. In 1973 outfits 1 to 10 were still available, but new kits were added: Army Multikit, Highway Multikit, Plastic Meccano, Pocket Meccano and two Clock Kits.

In 1978 the range of Meccano sets was further reduced and changed with the replacement of the No. 2 to 8 sets by six completely new sets, labelled A and 1 to 5. The old No. 9 and 10 sets were left largely unchanged.

By 1980 Airfix themselves were in financial trouble and, in an attempt to cut their losses, they shut down the Binns Road factory, bringing to an end the manufacture of Meccano in England. Meccano was, however, still being manufactured in France, although under the ownership of General Mills, a United States toy manufacturer since 1972.

In 1981 General Mills bought what was left of Meccano Ltd UK, giving it now complete control of the Meccano franchise. All the existing Meccano sets were scrapped and a totally new range of sets were designed for production in France called "Meccano Junior". These new sets included many plastic parts and could only build small models. Thus Meccano's concept of "Engineering in Miniature" was now completely lost and it was reduced to nothing more than a toy.

In 1985 General Mills sold out to a French accountant, Marc Rebibo, and, once again, all existing Meccano sets were scrapped. The "Meccano Junior" sets were replaced with three "Premier Meccano" sets and two "Motor" sets (including a six-speed motor) were introduced. Due to demand, the old Meccano No. 5 to 10 sets from 1981 were re-introduced.

In 1989 Marc Rebibo sold what remained of Meccano to Dominique Duvauchelle. Allen head zinc plated steel bolts replaced the original slot-headed brass-plated bolts and the "Plastic Meccano Junior" sets were brought back. With younger model builders in mind, many theme sets were also introduced, including a "Construction and Agricultural" series, "Space" models and "Dynamic" sets. The old-style No. 5 to 10 sets remained in production until 1992.

In 1994 additional theme sets were introduced and a pull-back friction motor was added to the Plastic Meccano System. In 1996 "Action Control" sets with infrared controls were added and 1999 saw the introduction of a "Motion System" range of sets that changed the look of Meccano completely.

There were six one-model sets, two five-model sets, and five new sets numbered 10 to 50, the 20 to 50 sets being motorized. A complete change from the normal practice (sticking to a single majority colour) was that every set had its own colour scheme, often in bright neon colours.

In 2000 Nikko, a Japanese toy manufacturer, purchased 49% of Meccano and took on its marketing internationally through its established channels for radio-controlled toys. Development and design remained with the 51% of Meccano SN, based in Calais, France. Nikko launched a successful range of new sets, including "Crazy Inventors" and the "Future Master" range.

Significantly, Nikko radio control and programmable electronics started to appear in the System. However, under commercial pressure, Nikko sold its interest in the Meccano name and System back to Meccano SN, the French parent company, in August 2007.

Meccano today is very different from its heyday in the 1930s to 1950s. The target market has not changed much (still youngsters). However, the mass market, instant-appeal approach does not always satisfy serious Meccano enthusiasts. For example, it is often difficult to obtain original spares.

Many parts were introduced since the Liverpool factory closed under the French-and-Japanese running of the company. These included plastic parts, gears, electric motors and battery boxes. Metal became an expensive raw material to work with and many of the metal parts were replaced with plastic parts.

Allen (hex-headed) zinc electroplated steel bolts replaced the slotted bolts. Die-hard enthusiasts from the declining height of the Meccano era are now in their 50s or 60s. Some of these Meccano modellers enthusiastically embrace the changes and new parts. However, the "purists" look down on these new parts. Some enthusiasts set self-imposed limits on using only parts deemed to be traditional and steer clear of those parts viewed as “not truly Meccano”.

Original specialist parts, such as very long (up to 2 foot) angle girders, loom shuttles, printing rollers, etc. often required for large Super Models are becoming more difficult to obtain. However there are replica manufacturers around the world who satisfy the need from enthusiasts who build legacy models that need these parts.

The current range of Meccano electric motors are small DC types designed to run on domestic batteries. These are low-torque high-speed "can" motors. These are inexpensive and suitable for small models that a child might construct from the standard range of sets.

Adult enthusiasts tend to use a wider range of high-performance motors that are better suited to powering large models. During Meccano's heyday, the electric motors on offer were universal wound (for use on DC or AC supplies). Particularly well known were the E020, E20R and E15R universal motors, and issued after the Second World War. These could be run from a mains transformer or, in the case of the E15R, a 12V car battery.

Earlier there had been short-lived (and potentially lethal) mains motors designed for DC mains with a domestic lightbulb in series to drop the voltage, followed by motors of the post-War pattern but wound for 4.5 or 6V DC and suited to lead/acid accumulator power. These, as well as the latter accumulator are now rare if in good condition.

What has remained the same during all these years, is the Imperial ½ inch perforation spacing and the 5/32 inch nut and bolt whitworth threads. Meccano must be one of the very few products which have maintained identical standards and complete interchangeability of parts from its commercial inception in 1901 right through to the present day. Many modern models function perfectly with Meccano components that are more than 100 years old.

Some model construction kits are compatible with Meccano. One example is the Swiss brand Stokys, which has been manufactured since 1941. Their elements are mainly made of thick stable metal in order to fit to the general approach of Swiss Quality. Other examples are Exacto and Metallus.