KKKK
2222
TTTT
AA88

Cryptography is the study of techniques used for secure communication
For information security you need to be able to store passwords or exchange
 information such as messages securely between computers which relies on
cryptography to keep the information safe.
Before the digital age cryptography primarily referred to the encryption and
decryption of messages to and from text intended to be indecipherable except
by the intended recipients.
With the computer era cryptography is much more math-heavy.
Various encryption models or protocols were designed for
transmission of electronic data including the Data Encryption Standard by IBM.
Following their work, an encryption algorithm is considered secure enough if
it is mathematically difficult enough to decode.
The computational hardness assumption assumes that attackers or eavesdroppers
don't have unlimited computing resources to decode your communications.

With symmetric-key cryptography the sender and receiver of a message use the
same key to encrypt and decrypt a message. This can make it difficult when
trying to make messages secure among many people as every distinct message
between a pair of users or group of users would need a distinct key.
In public-key cryptography, a public key is used to encrypt data while a private
key is used to decrypt it; the two keys are mathematically related while also
not simply being able to be determined from the other one.
hashing is a type of encryption that scrambles input and cannot be reversed easily,
however, by using something called rainbow tables, password crackers
store the output of many common passwords put through common hashing algorithms
allowing weak passwords to be reverse-looked up in these tables.

secure messaging apps such as telegram automatically use cryptography to make
sure your information is secure.
when working with cryptography the goal is closely tied to information security:
you want to be able to make sure users can only access data they have permission
to access with data confidentiality,
you want to make sure users are who they say they are;
you want to make sure that data is not lost when encrypting it
and for some applications you want to make sure some user actions or messages have
a signature attached that proves it was sent by a specific person:
for example, if I agree to pay someone for a service over electronic communication
and sign it digitally, I shouldn't be able to go back and say that I never made
an agreement.

defensive strategies to avoid cryptography include
not using websites that store passwords in anything other than plain text
as websites use encryption to prevent anyone from seeing your password.
even if they "store" your password in a database, it's going to look
like jibberish
in fact, most of the internet uses encryption to a degree
but maybe "how do I avoid cryptography?" isn't the question
we shouldn't be asking here

to avoid cryptographic vulnerabilities, companies should
implement well-tested algorithms instead of designing their own
such as AES, RSA or SHA-256.
data should be secure not only during transmission but also during storage
as message sending is not the only time data can be vulnerable.
companies also should keep track of machine identities and signatures
so hackers cannot create encrypted tunnels to hide in.