Before anything else: what is cryptography? Well, it’s basically the art (or science) of keeping secrets. It involves using mathematical techniques to encode information in such a way that only authorized parties can access it. This is important for all sorts of reasons from protecting sensitive data like bank account numbers and medical records to ensuring secure communication between government agencies and military forces.

Now, some basic concepts you need to know before we get into the details. First up: encryption and decryption. Encryption is the process of converting plaintext (readable text) into ciphertext (unreadable text). This can be done using a variety of techniques, but one common method involves substituting each letter in the message with another symbol or number. For example, you might replace every “A” with a “#”, every “B” with an “@”, and so on.

Decryption is just the opposite it’s the process of converting ciphertext back into plaintext. This can be done using a key (or decryption algorithm) that allows authorized parties to unlock the message. The key might involve reversing the substitution method used during encryption, or it might involve using another mathematical technique altogether.

Another important concept in cryptography is hashing. Hashing involves taking an input (like a password or a file) and producing a fixed-size output that represents that input. This can be useful for things like storing passwords securely instead of storing the actual password, you store its hash value. When someone logs into your system with their username and password, you hash the entered password and compare it to the stored hash value. If they match, then the user is authenticated!

Finally, some common encryption algorithms that are used in cryptography today. One popular algorithm is AES (Advanced Encryption Standard), which uses a combination of substitution and permutation to encrypt data. Another algorithm is RSA (Rivest-Shamir-Adleman), which involves using two large prime numbers to generate public and private keys for encryption and decryption.

Of course, this is just scratching the surface there’s so much more to learn about this fascinating field. But hopefully, we’ve given you enough information to get started on your own cryptographic adventures.