python

In Post #25, we took a major step in controlling our program’s flow with the if statement. We learned how to execute a block of code only when a condition is True. This is powerful, but it leaves a question unanswered: what happens if the condition is False? Currently, our program just silently skips the … Read more

For the last four posts, we have been assembling our logic toolkit: Booleans (Post #21), comparison operators (Post #22), logical operators (Post #23), and the concept of Truthy/Falsy values (Post #24). It is now time to use these tools to control the very flow of our programs. In this post, you will learn how to … Read more

In our exploration of logic, we’ve focused on the explicit boolean values True and False (Post #21) and how to generate them with comparison (Post #22) and logical operators (Post #23). Now, we’re about to uncover a feature that makes Python’s logic especially elegant and concise. This post explores the key Python concept of Truthy … Read more

In Post #22, we learned how to ask simple questions using comparison operators, resulting in a True or False value. This is a great start, but real-world logic is often more complex. We frequently need to check multiple conditions at once. For example: Is the user over 18 and a resident of this country? Does … Read more

In Post #21, we established that Boolean expressions are the “questions” our programs ask to get a True or False answer. Now, it’s time to learn the language for asking those questions. How do we ask if two values are the same, or if one is larger than the other? This is where comparison operators … Read more

Welcome to Part 2 of our Python series: Logic and Control Flow! In Part 1, we built programs that were like a set of instructions read from top to bottom. They were powerful, but they followed the same path every time. Now, we’re going to learn how to make our programs “think”—how to make decisions, … Read more

Congratulations on reaching the end of Part 1 of our Python series! This is a major milestone. You have journeyed from understanding what Python is, to writing your first interactive scripts, and you’ve picked up an entire toolkit of fundamental concepts along the way. In this post, we will first briefly recap the core concepts … Read more

Since we were introduced to variables in Post #8, we have been using the single equals sign (=) constantly. This is the assignment operator, and its primary job is to assign a value to a variable. But what happens when we want to modify a variable’s existing value, for example, by adding to it or … Read more

In Post #17, we learned how to build strings by concatenating them with the + operator. While it works, you probably noticed it can get a bit messy, with lots of quotes, plus signs, and calls to str(). It’s easy to forget a space or a + and get an error. Thankfully, modern Python (version … Read more

In Post #16, we encountered a surprising behavior. When we tried to add two numbers received from input(), our program produced “57” instead of 12. We learned this happened because the + operator, when used with strings, doesn’t perform mathematical addition—it joins them together. This process has a formal name: concatenation. In this post, we’ll … Read more