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WonderTechnology fact

Creeper, written in 1971, is generally seen as the first computer worm: a program that copies itself from one computer to another across a network. It did no harm, and simply printed 'I'M THE CREEPER: CATCH ME IF YOU CAN' on each machine it reached.

Technology history

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Bob Thomas wrote Creeper at the Massachusetts firm BBN as an experiment on ARPANET, the US research network that grew into the internet. His first version moved from one computer to the next; Ray Tomlinson, the engineer who created network email that same year, changed it so that it copied itself instead. It could reach at most 28 machines, the number on ARPANET then running the TENEX operating system. In 1972 Tomlinson wrote Reaper, which travelled the network deleting Creeper and is often called the first antivirus program. A worm differs from a virus: a worm spreads on its own, while a virus hides inside other programs or files and spreads when they are run. Harmful worms came later; the Morris worm of 1988 disabled thousands of computers on the early internet.

Türkçe oku
1971'de yazılan Creeper, genellikle ilk bilgisayar solucanı sayılır. Solucan, bir ağda kendini kopyalayarak bilgisayardan bilgisayara yayılan programdır. Creeper hiçbir zarar vermedi; ulaştığı her makinede yalnızca “I'M THE CREEPER: CATCH ME IF YOU CAN” (Ben Creeper'ım, yakalayabilirsen yakala) yazısını yazdırdı.

Creeper'ı Bob Thomas, Massachusetts'teki BBN şirketinde, internetin öncüsü olan ABD araştırma ağı ARPANET üzerinde bir deneme olarak yazdı. İlk sürüm bir bilgisayardan ötekine taşınıyordu; aynı yıl ağ üzerinden e-postayı geliştiren mühendis Ray Tomlinson, programı taşınmak yerine kendini kopyalayacak biçimde değiştirdi. Creeper en fazla 28 makineye ulaşabilirdi; ARPANET'te o sırada TENEX işletim sistemini çalıştıran makine sayısı buydu. Tomlinson 1972'de, ağda dolaşıp Creeper'ı silen ve çoğu zaman ilk antivirüs programı sayılan Reaper'ı yazdı. Solucan ile virüs aynı şey değildir: Solucan kendi kendine yayılır; virüs ise başka programların ya da dosyaların içine gizlenir ve onlar çalıştırıldığında yayılır. Zararlı solucanlar sonra geldi: 1988'deki Morris solucanı, o dönemin internetindeki binlerce bilgisayarı kullanılamaz hâle getirdi.

Sources and further reading

Background reading: Creeper and Reaper
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