A list is a data structure in python which stores a sequential collection of elements of any size. Each element or value that is inside of a list is called an item.

• A list is flexible i.e. does not have a fixed size.
• A list is mutable i.e. the contents of a list can be changed.
• A list can contain elements of same or mixed types.

  Creating a list

• empty list

list = [ ]

• list with integer elements

list = [ 2, 3, 4, 5]

• list with string elements

list = [ "red", "blue", "pink"]

• list with elements of mixed type

list = [ "red", 2, 5]

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Built-in list functions

• len() : To find the length of a list.
• max() : To find the largest element in a list.
• min() : To find the smallest element in a list.
• sum() : To find the sum of all elements in a list.
• random.shuffle() : To randomly shuffle the elements present in a list.

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List operators

• Index operator : To access an element in the list from its index. Python also allows the use of negative numbers as indexes to reference positions relative to the end of the list.

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Accessing a list out of bounds is a common programming error that results in a runtime IndexError. To avoid this error, make sure that you do not use an index beyond len(list) – 1.

Often reference to the first element in a list is mistaken with index 1, but it should be 0. This is called the off-by-one error.

• Slicing operator : The slicing operator returns a slice of the list using the syntax list[start : end]. The slice is a sublist from start index to index end – 1. You can also use a negative index in slicing.

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• Concatenation operator (+) : To concatenate or join two lists.

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• Repetition operator (*) : To replicate elements in a list.

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• in and not in operator : To check for the presence of an element in a list.

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• Operators for comparing lists : (>, >=, <, <=, ==, and !=)

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  List methods

• append() : To add an element to the end of the list.
• count() : To return the number of times an element appears in the list.
• extend() : To append all the elements of a list to another.
• index() : To return the index of the first occurrence of an element in the list.
• insert() : To insert an element at a given index in the list.
• pop() : To removes the element at the given position in the list and return it.
• remove() : To remove the first occurrence of an element from the list.
• reverse() : To reverse the elements in the list.
• sort() : To sort the elements in the list in ascending order.

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  Splitting a String into a List

  The split method is useful for splitting items in a string into a list. One can use either a space or a non-space delimiter.

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  Copying lists

  A list can be copied to another using the assignment statement (=). However, this statement does not copy the contents of the list referenced by list1 to list2; instead, it merely copies the reference value from list1 to list2. After this statement, list1 and list2 refer to the same list. The list previously referenced by list2 is no longer referenced; it becomes garbage.

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Happy coding !!