 When we deal with numbers and call functions to work with the numbers, we specify an action and give it a value to work with. For strings, the length function works that way, but it's an exception. Unlike integers, floats, and booleans, strings are objects, and most of the time the string is the lead character in our drama, and we tell the actor, the string, what action to perform. In this case, create an all uppercase version of the string. When an object says what function to perform, we call that function a method, and we separate the object from the method with a dot. Let's go to Python to run through a laundry list of some of the more important string methods. We'll start with methods that give us a new version of a string. Let's set S to be Python strings with an exclamation point. The upper method, S.upper, converts all the letters to uppercase. S.lower invokes the lower method to set all the letters to lowercase. It's important to note that these methods, and all the other string methods, give us back a new string. S.upper gave us back a new all uppercase string. S.lower gave us a new all lowercase string. S itself never got changed. In programs just the way absolute value of X doesn't change X, it gives back a new number that we have to assign to a variable. When we're in a program, and we call the upper method, it won't change string S. It'll give us back a new string that we're going to have to assign to some variable. Sometimes you'll have strings with extra blanks at the beginning or end. Let's create a string that has extra blanks at the beginning and at the end. The strip method will give us back a new string with the leading and trailing blanks removed. The L strip method will give us back a new string with the leading blanks at the left removed. And the R strip method will give us back a new string with the trailing blanks at the right removed. There are also methods to let you search and replace parts of a string. Let's set our string to this and that. If you want to find out how many times an item appears in a string, you can tell string S, please give me a count of the number of times the letter H occurs, which will be two. Or if I want to find out how many times the word and appears, it appears once. If I give something that doesn't appear in the string at all, I'll get back zero. More often you'll want to know where an item is found in the string. The find method gives the leftmost index where the substring item was found. S.find with the string is begins at position two. If the item you want to find isn't inside the string, you get back a position of negative one. The R find method will find the index where the rightmost occurrence of a substring begins. The rightmost th begins at index nine and again returns negative one if the substring is not in the string at all. Finally, we can replace one substring by another. Let's create a new string here and get a new string where we've replaced all occurrences of t with g or one where we replace all occurrences of comma followed by space with three dashes. These are some of your main string methods. In the next video, we'll use some of them in a program.