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15 results for “JavaScript”
JavaScript
Bring the web to life, one line at a time.
LessonJavaScript: Your first program
A program is a set of instructions. Start with one instruction that prints a message. Run it, change the message, and run it again. The edit–run–observe loop is how progr…
LessonJavaScript: Variables & values
A variable gives a name to a value. Choose names that describe the information, such as score or learner_name. Assign a value before you read it, and remember that assign…
LessonJavaScript: Working with data types
Numbers, text, and true-or-false values behave differently. Adding numbers calculates a sum; combining strings joins text. Convert a value deliberately before using it in…
LessonJavaScript: Operators & expressions
An expression produces a value. Arithmetic operators combine numbers, and comparison operators answer questions. Parentheses make the intended order explicit and help the…
LessonJavaScript: Making decisions
A conditional chooses an action based on a true-or-false expression. Think about the boundary: does a score of exactly 10 belong in the first branch? Test values below, a…
LessonJavaScript: Repeating with loops
Loops apply the same steps to many values. Start with a small collection so you can follow each iteration. A loop must eventually finish; make sure its condition or seque…
LessonJavaScript: Your first function
A function packages a useful operation under a name. Parameters supply input, and a return value carries the result back to the caller. Keep printing separate from calcul…
LessonJavaScript: Arrays & lists
A collection groups related values in a particular order. Indexes start at zero in these languages. Check whether a collection is empty before accessing its first value, …
LessonJavaScript: Working with strings
Strings represent text. Text can include spaces, digits, or punctuation. A character position is an index; a substring is a selected part of the text. Keep the original v…
LessonJavaScript: Handling errors
Failures are part of a program, not an unusual exception to learning. Catch a specific failure near the operation that can fail. Give useful feedback and preserve enough …
LessonJavaScript: Objects & classes
Objects group data with related behavior. A class describes how to create those objects. Model a small concept first, such as a learner with a name and a greeting, and ke…
LessonJavaScript: A first algorithm
An algorithm is a repeatable procedure for solving a problem. Counting values is one example: begin with zero, inspect each item, and update the count when it matches. Ch…
LanguageTypeScript
Make JavaScript more predictable.
RoadmapFull Stack Developer
Connect the dots from a web page to a complete app. HTML Foundations CSS & Responsive Layouts JavaScript Git & Collaboration React Node.js Databases & APIs Deployment