Strings in Python
Strings in Python - Bytesize Python
Why Strings?
Creating a String
To create a string, you can often assign it to a variable. A string might include letters, numbers, symbols or spaces. These are called characters. (You may have seen this in the Variables in Python or Data Types in Python page)
Adding strings
Adding numbers together results in another number. Similarly when adding strings, they simply join on to the end of the other.
You can also add a string in between the variables.
Length of a string
The 'len()' function is used to find out the length of a string. Python counts all of the characters, including spaces, and gives the total number of characters.
Numbering characters
Each character in a string is allocated a number according to its position. The position number is called an index. Strings always start with the first character having an index of 0, and then going on from that. For example a character with the index of 4, with be the 5th letter in the word.
C A T E R P I L L A R
0 1 2 3 4 5 6 7 8 9 10
Two Indexes can be used to pull out part of a string or slice it. The last index you give will not be included, so in this example only indexes 1,2 and 3 will be shown. If you leave out the start or end index, python will automatically include the first or last index.
Apostrophes
You may have noticed that I tend to put single quotation marks around my strings, however you can also use double quotation marks if you prefer. But if you choose to use single quotation marks like me, you may wonder how you can use apostrophes in strings. If you add a backslash before the apostrophe, python will interpret it as part of the string and not the end of the string. This is called escaping it.
