Source: https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-2-1-input-and-output [Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [GCSE](https://senecalearning.com/en-gb/revision-notes/gcse.md) › [Coding](https://senecalearning.com/en-gb/revision-notes/gcse/coding.md) › [National Curriculum](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum.md) › Input & Output # Input & Output Coding: Introduction to Python v3, topic 1.2.1 ## Input There must be some mechanism for the user to input data to the computer. ### What data can I input? ![What data can I input?](https://image-v2.cdn.app.senecalearning.com/2018-08/896bfbb3-c1ee-4792-89b4-6bedd4f46136/metadata-data-.jpg) - Data can be input from any device connected to the computer. - The keyboard is the most common data input device for command line programs. - We will only look at keyboard input in this course. ### The input function ![The input function](https://image-v2.cdn.app.senecalearning.com/2018-05/5a9662ab-b70b-4e5b-911b-d70513b89d02/shutterstock_747571558.jpg) - Python has a built in function (command) which allows us to take keyboard input. - We can use the code: input(“Prompt”) to take the input. - We can write any text for the “Prompt”, which will be displayed to the user before they type their response. - A prompt is a message that is displayed to the user before they type their response. ### Data type of input ![Data type of input](https://image-v2.cdn.app.senecalearning.com/2018-08/6678c24d-96b2-4f4b-8c75-3883dade05bf/corrupted-data-.jpg) - When data is entered from the keyboard, it is automatically a ‘string’. - A string is a sequence of character inputs from the keyboard, for example ‘Hello’. ## Output Output is necessary so that we can see the results of programs. ### Why do we need outputs? ![Why do we need outputs?](https://image-v2.cdn.app.senecalearning.com/2018-09/2d01dd30-e1e4-455b-b291-78ae3261cb96/tv-child-watch-boy-.jpg) - Outputs are important so that we can communicate the result of a program to the user. - Outputs are usually delivered as text onto the screen. ### The print function ![The print function](https://image-v2.cdn.app.senecalearning.com/2018-08/2cab83d7-a047-4490-bdf0-ce2e662f6d26/printing-press-print-.jpg) - The output function in Python is called ‘print’. - The output function ‘prints’ data onto the screen. - E.g. print(“Hello, world!”) would output the text “Hello, World!”. ### What data can be outputted? ![What data can be outputted?](https://image-v2.cdn.app.senecalearning.com/2018-07/1067548c-e876-492c-a3c9-a8b266f0b1e6/Manipulation-Puppet-Strings-.jpg) - Output data must be a string before we can print it. - If we want to combine non-string data with text, we must first cast it to a string. - Otherwise, print() can display non-string data directly. ## Test yourself on Input & Output - What is the most common input device for command line programs? - What data type is keyboard input? - Data can only be input from a keyboard. True or false? - How are outputs usually delivered in a command line program? - Why are output statements used? [Practise this topic for free](https://app.senecalearning.com/classroom/course/72d0364c-db0a-4630-8e0a-61f48cae0252/section/88b6911b-5c00-4ba9-92dc-78ff692ce926/session) - Previous topic: [1.1.1 Python](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-1-1-python.md) - Next topic: [1.3.1 Data Types](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-3-1-data-types.md) ## Coding: Introduction to Python v3 contents ### 1 Introduction to Python - 1.1 Python - [1.1.1 Python](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-1-1-python.md) - 1.2 Input & Output - [1.2.1 Input & Output](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-2-1-input-and-output.md) - 1.3 Data Types - [1.3.1 Data Types](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-3-1-data-types.md) - 1.4 Variables & Constants - [1.4.1 Variables & Constants](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-4-1-variables-and-constants.md) - 1.5 Operators - [1.5.1 Arithmetic & Relational Operators](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-5-1-arithmetic-and-relational-operators.md) - [1.5.2 Boolean & Assignment Operators 2](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-5-2-boolean-and-assignment-operators-2.md) - 1.6 Program Flow - [1.6.1 Selection](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-6-1-selection.md) - [1.6.2 Iteration](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/1-6-2-iteration.md) ### 2 Data Structures - 2.1 Lists & Strings - [2.1.1 Lists](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/2-1-1-lists.md) - [2.1.2 Strings](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/2-1-2-strings.md) - 2.2 File Handling - [2.2.1 File Handling](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/2-2-1-file-handling.md) ### 3 Modularity - 3.1 Subroutines - [3.1.1 Subroutines](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/3-1-1-subroutines.md) - 3.2 Data Flow - [3.2.1 Data Flow](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/3-2-1-data-flow.md) ### 4 Good Practice - 4.1 Naming & Whitespace - [4.1.1 Identifiers](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/4-1-1-identifiers.md) - [4.1.2 Whitespace](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/4-1-2-whitespace.md) - 4.2 Comments - [4.2.1 Comments](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/4-2-1-comments.md) - 4.3 Exceptions - [4.3.1 Exceptions](https://senecalearning.com/en-gb/revision-notes/gcse/coding/national-curriculum/4-3-1-exceptions.md)