Hey everybody and welcome back.
So this and this video we're gonna be talking about hashing.
So what is hashing hashing transfers plain text or some sort of text into a shorter representation of
itself.
Now it's important to understand that hashing is not like encryption hashing is a one way street.
It is when you hash something.
The point is is to not reverse it back.
So this is also called a hashing function.
So why why do you want to do this now.
This is commonly used in things that store in systems that store passwords so you don't want to store
the password in plaintext so what you do is you hash the password and then when it's stored there nobody
can even if somebody accesses the database.
They can't reverse the hash.
Now there are things called look up tables where people take you know known passwords hash them with
a certain algorithm and then they keep that in a database.
So it might be possible that your hash of what are your plaintext when it goes to a certain hash might
be available on the internet somewhere.
But in most cases when it's on a database for example the passwords been hashed when you set it and
then it just sits there it sits there in the database hashed and this is important because if somebody
grabs a hold of it they can't reverse it.
So they have to do a lot of things to break it which will go over in are password cracking module but
it's also it's important to understand that it's done that way for a reason.
You've meant to do it one way.
So when you sign in and put your password in to log in it takes that password runs it through the hashing
function and then compares what you sent versus what it has.
And that's how things log in.
Now it also works as for indexes.
So if you have something that is a larger index let's say it could be 50 100 200 characters long and
that's your index value for a database or whatever you're building you want that to be a shorter index
but you want it to be unique for that because it still is an index.
So you would hash your value into a smaller number which in turn gives you your your index that you
can use also used for file signatures such as you might have seen or heard referrals of you know give
me the empty five of the file so you can confirm that what you've downloaded is what they had.
So nothing got mangled during the download process.
This is pretty common in computer forensics is also done for the hard drive itself.
They get a full empty five hash at the end of the harddrive itself so that they can compare that nothing
changed from one step to the next.
So it's got a lot of important use cases.
So what are some types of hashing MDT five as one shot has multiple different versions and entail it.
Now we're going to go over MDG 5 and shore in this particular course we won't touch and tell him in
great detail but we will cover it a little bit more in other videos when we go over like the password
cracking module.