Python is a

• dynamically typed language - variable types are assigned at runtime
• Interpreted language - code is compiled and executed line by line
• Strongly typed - No type coercion

Python gives us high level functions and operations to do things that might take 10-15 lines in C.

In the interpreter…
Unless defined, the _ character keeps the result of the last value

Fun fact: Python was written in C

String Indexing

your_string = "hello"

We can extract part of a string FROM an index to the end
> your_string[2:] == "llo"

We can also extract part of a string FROM an index TO a limit (not including the limit index)
> your_string[1:4] == "ell"

We can step every n elements of a string
> your_string[::2] == "hlo"

We can extract part of a string, and also step
> your_string[0:4:2] == "hl"

We can reverse a string with a negative step
> your_string[::-1] == "elloh"

(Im)mutability

Strings are immutable (cannot change a letter by its index)

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string_variable = "Hello, World!"
string_variable[1] = "Z"
# TypeError: 'str' object does not support item assignment

Lists are mutable though!

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string_variable   = "Hello, World!"
list_of_string    = list(string_variable)
list_of_string[1] = "Z"
"".join(list_of_string)
# HZllo, World!