 Okay, hopefully I say everything right in this tutorial. I've actually started to record it three times and I keep saying the wrong things because I just get them mixed up in my head. But basically let's create a variable here as we have in previous tutorial. We'll say, hello world. And as we've done in the previous tutorials we've been working with the case of the letters. We can say echo and if we just echo out the variable obviously it's gonna say hello world. But we've learned if we put this into curly braces and do comma, comma, it lower cases everything. It takes everything and makes it lower case. And we do the carrots, it makes everything uppercase. Well recently I discovered that let's say let's say our variable was all lower case. So we're gonna set x equal to hello world all lower case. And obviously I said if we do carrots everything's uppercase but if we do the same thing with one carrot it actually affects only the first letter in our string. If we go in here and we do, well let's change the value of our variables again. We'll say x equals hello world all upper case. If we echo out x and we do a single comma instead of making everything lower case it makes the first character of the entire string lower case. Now we can also do the same thing with the tilde which is on US keyboards top row to the left of the one on the same key as the back tick. If we hit that it will actually, in this case it looks like it's making the first character of each word in the string lower case but what it's actually doing is reversing the case. So if we were to change this to be a lower case w and we run that we now have a capital H, I'm sorry low case H and a capital W because it's actually reversing the first character of each word in the string. Unlike the using the carrot and the comma which is affecting the first letter in the entire string this is affecting the first character in each word within the string. And it's not making it capital lower case it's reversing it. We could also do two tilde's and hit enter and right now you look at it and what it actually did was it reversed every character's case in the entire string. So let's go in here and we'll change this to lower case E, lower case L we'll make this a lower case L. So now if we do that it's printing out the entire string but reversing the case of every character within the string. So as you can see and get a little confusing that's why I screwed up this drill the first three times I was trying to record it because I just getting all mixed up in my head but quickly let's review. If you echo out the value of the variable you get the value of the variable. Two commas within these curly braces it makes everything lower case. To carrots it makes everything uppercase. If we do a single carrot it will make the first character within the entire string whether it's capital or a case it will make sure it's capital. If you do a comma it will make the first character in the entire string lower case. If we do a single tilde in there it will make the first letter of each word the opposite of what it is. So if it's lower case it will make it uppercase and uppercase it will make it lower case for every, the first letter of every word in the string. And if you do two of the tildas it will reverse every character in the string to the opposite case. So uppercase characters go lowercase and lowercase go uppercase. So I think I said everything right that time. I sure hope you enjoyed this tutorial. Please visit filmsbychrist.com that's Chris with a K. There should be a link in the description. I hope you're enjoying these tutorials and I hope that you have a great day. Be sure to like this video if you're enjoying these bash tutorials so that I know what you guys like. Thank you for watching and have a great day.