NaN means “Not a Number.” It happens when a calculation does not give a real number. For example, dividing zero by zero or taking the square root of a negative number can create NaN. In Dart, NaN is a special value used to show that a number is not valid. It helps your program know […]

An empty string means the string has no characters at all — it is just “”. It’s like having a box with nothing inside. Checking if a string is empty helps in many situations. For example, when asking for user input, you want to know if the user typed anything or left it blank. It

Converting strings to numbers means changing text that looks like a number—like “123” or “3.14”—into actual number values that your program can use for math or calculations. This is useful when you get input as text, for example, from users typing in a form or reading data from files. To work with these inputs as

Converting numbers to strings means changing a number like 123 or 4.56 into text that looks like “123” or “4.56”. This helps when you want to show numbers in messages, print them, or join them with words. You might want to convert numbers to strings when building apps, writing messages, or formatting data for display.

In Dart, asynchronous means something that doesn’t happen right away — it happens later. For example, waiting for a message, loading a file, or getting data from the internet. Dart uses three main tools for this: async, await, and Future. These help your program keep running while waiting. This is useful when you don’t want

Dart is a programming language made by Google. It is used to build fast and good-looking apps for mobile phones, websites, and computers. If you’ve used Flutter, you’ve already used Dart. In Dart, you work with classes to create objects. A class is like a recipe — it tells the computer how to make and

In Dart programming, an interface is a way to set rules for classes. It defines a list of method names that a class must have, but does not include the method’s actual code. You can think of an interface as a promise a class makes to perform certain actions. This helps different classes follow the

When working with strings in Dart, it’s common to encounter extra spaces at the beginning or end of the text. These spaces, known as whitespace, can sneak in when users input data or when strings come from external sources. This is where string trimming comes into play. Trimming strings is a process that removes unwanted

In Dart, a mixin is a special kind of class that lets you share code between multiple classes without using inheritance. Think of it like a toolbox of reusable methods and properties that you can “mix into” any class. You use the with keyword to add a mixin to a class, and just like that,

Sometimes in programming, we don’t care whether a number is negative or positive — we just want to know how far it is from zero. That’s where absolute value comes in. What is Absolute Value? In simple terms, the absolute value of a number is how far it is from zero, ignoring the sign. So