Cryptography - simply explained
When it comes to data protection, internet security and file encryption, the term cryptography is often used. In this practical tip, we explain what exactly is behind it.
Cryptography simply explained: what is it actually?
The Greek term cryptography means cryptography. So it's a science that mainly involves encrypting text and other files. This is to prevent unauthorized access.
- It is evident that the first texts were encrypted in the third millennium BC. Both in the Roman Empire and in the Middle Ages, important messages or war orders were encrypted using cryptography.
- Julius Caesar used a very simple form of cryptography for his messages. Each letter has been replaced by the third next letter in the alphabet. So instead of an A, a D was written. The recipient of the message had to know that it was a three letter shift and could therefore make the D an A again.
- Machines for encrypting messages were already used in the Second World War. Cryptography became significantly more complex, so it took the British several years to crack the key and read the news in plain text.
Cryptography in the digital age
The increased computing power of computers has made cryptography significantly more complex, but it has also become much more secure. Encryption like you used to use Caesar is cracked within seconds.
- Wherever data protection is concerned, cryptography is also an important topic. If you log on to a website with your password, this is usually done in encrypted form. You can also send your mails or WhatsApp messages in encrypted form. Encryption is also possible to make tap-proof calls.
- In modern cryptography, a distinction is made between symmetrical and asymmetrical encryption. With symmetric encryption, sender and recipient use the same key as with Caesar encryption. To do this, the key must be known to both people and transmitted verbally or unencrypted.
- With asymmetric encryption there is a public and a private key. With the public key, every user can send you an encrypted message. However, the message can only be decrypted using the private key.
- Cryptography knows many different methods for encrypting a file. Many methods are based on complex mathematical structures such as elliptic curves, rings and finite fields. A deep understanding of mathematics is therefore necessary to develop complex cryptography.
In the next practical tip, we will explain what cryptocurrency has to do with cryptography.