For cryptocurrency Ethereum there are many purses you can use to generate private keys. But the whole point of creating the private key be to ensure that we get a unique number in hexadecimal. The number looks something like this: d7c9533613bb756ddf64d250dfe56f6d2d1333ab6b69e8d5635046197c430a31 as we see this is a character set consisting of 64 characters which include numbers from 0 to 9 and the first 6 letters of the Latin alphabet.
Irreversible hash functions also consist of a set of characters belonging to the hexadecimal number system. If we take such a well-known hashing algorithm in the cryptocurrency world as SHA256, then we will see that the Ethereum private key and the SHA256 hash amount are identical in structure. They both have a number consisting of 64 characters in hexadecimal number system. Hash sums are also called checksums., but essentially it's the same thing.
To create an Ethereum private key in a non-standard way, we will need any file with any extension and any size. We obtain the checksums of this file using the SHA256 algorithm and have a private key that can be imported into any wallet, which in turn will give us the address to receive funds from our newly created private key. Programs for obtaining checksums are easy to find for any OS., even for Android.
With this method of creating a private key, it is worth mentioning security measures. Since it would not be reasonable to create a private key by obtaining checksums of some popular file downloaded from the Internet, simply because by downloading this file, not only you can get the hash of this file and use it as a private key.
This is of course unlikely, that someone will try to do the same, but it's still worth remembering. It would be best to create your own unique file, eg, a simple text file with unique content can already serve as a fairly reliable choice. It is important to make backup copies of such a file and store it in a safe place, and ideally also encrypt.
Of course, few people will use this method in practice., but it is quite working and, with the right approach, can be no less reliable than using Ethereum wallets specially designed for this or storing it on cryptocurrency exchange.
For example, the SHA256 hashing algorithm was taken since it is more familiar to people than other algorithms of which there are many. You can generally use any algorithm that consists of 64 characters in hexadecimal number system. We also took the Ethereum cryptocurrency as an example., but if you look deeper, that is, other cryptocurrencies in which private keys can be created using the same method.