In programming, we store data into variables.
Think of a variable as a box for information.
You might put books, linen, microwaves, and so on into a real-world box. In the programming world, all those physical objects would be replaced by data.
If you had a garage full of boxes and wanted to find the one containing books, you'd probably look for the one with the label "Books".
Programs are no different. In order to distinguish a variable from another, we label it with a name.
This helps us know what kind of data is contained in a particular variable.
Make sure to use descriptive names to help out anyone (including yourself at a later time) understand what information is contained in a particular variable.
💡 Think of a variable as a labeled box that holds some data.
To get us started, let's say that we have the text "Enki" as our data, and we want to store it in a variable named study_buddy:
💡 Unlike human names, variable names cannot hold spaces. Common naming conventions for multi-word variable names are to use snake case (study_buddy) or camelCase (studyBuddy).
In programming, putting data into a variable is usually done with the = sign:
💡 Don't worry about the quotation marks around "Enki" for now. We'll explain them in the insights coming up.
Putting data into a variable is called an assignment.
💡 Assignment is usually done right to left. Using "Enki" = study_buddy will not work.
Data Types
You can think of a data type as a category for information.
Just like how in most human languages a "house" and a "skyscraper" are both in the category of "building", in programming languages a 1 and 0xff¹ are both in the category of "number".
💡 Don't worry too much about the strange-looking 0xff. The core idea to focus on is that programs categorize data by type.
Most programming languages support at least some data types. The most common ones are:
- number
- text
- boolean
- list
- dictionary
There are many more types, (and you can even build your own!) but you'll start learning them as you dive into a specific programming language.
Data types are very important! They decide what actions you can and cannot take for a particular value. One example is that you can't add the number 1 to the text "one".
Footnotes
[1] Computers commonly represent data using a hexadecimal system of 16 digits, unlike our everyday decimal system of 10 digits.
The 6 digits after 0-9 in hexadecimal are actually the letters a-f.
Using a system of 16 digits allows us to present more information with fewer characters.
Check out this article for more info
