Although the development of the computer has been largely played out during the 20th century, there is a long history of automatic calculation. Among the earliest electronic computers were the Colossus series of special-purpose computers, developed secretly in the UK from 1943. A new era for reliable software started by using small layers of software above the hardware and by developing the microcode it enabled the computer to execute a larger set of instructions, which allow reading from and writing to files, input/output devices. This is provided by the compiler or interpreter, which permits a programmer to write programs in a problem-orientated computer language. Such a development of software engineering made the design and implementation a less error-prone process. The major challenges for the future of computing and the programs include the development of even higher level computer languages for the in-depth Internaut surfacing, and artificial intelligence thus being closer to human behaviour.