JavaScript const vs var: Understanding the Difference
In JavaScript, both const and var are used for variable declarations, but they behave differently var is function-scoped, meaning it is accessible within the function where it is declared, even if declared inside a block const, on the other hand, is block-scoped and cannot be reassigned once defined Using const helps prevent accidental changes to variables, making the code more predictable and less error-prone javascript const vs var .

Map vs forEach in JavaScript: Which One to Use
Both map and forEach are used for iterating over arrays in JavaScript forEach is used to execute a function on each array element but does not return a new array, making it suitable for performing side effects like logging or modifying elements in place map, however, returns a new array with the results of applying the function to each element, making it ideal when transformation of data is required

Sorting in Python with the Key Parameter
Python’s built-in sort() function and sorted() method allow sorting of lists with a customizable key parameter This parameter is a function that determines how elements should be compared, making sorting flexible For example, sorting a list of strings by their length can be done using sorted(my_list, key=len) This method allows efficient and readable sorting tailored to specific needs

Setting Cookies in JavaScript
Cookies are small pieces of data stored in the browser, often used for authentication and user preferences In JavaScript, a cookie can be set using document.cookie For example, document.cookie = "username=John; expires=Fri, 31 Dec 2025 12:00:00 UTC; path=/" sets a cookie that expires at the specified date Managing cookies correctly is important for web security and user experience

Handling Cannot Read Property of Undefined Errors in JavaScript
The error Cannot read property of undefined occurs when trying to access a property on an undefined value This usually happens due to incorrect object references or missing data To prevent this error, use optional chaining (obj?.property) or check if the object exists before accessing its properties Using default values and debugging with console.log() can also help identify the source of the issue