Working with Variables in JavaScript

Now that we've tried storing values in variables, 0:00 let's practice using variables in ways we might while programming with JavaScript. 0:03 Earlier I mentioned that the number type in JavaScript allows you to perform 0:07 mathematical operations. 0:11 Based on what you learned in the last video, try creating two variables and 0:13 assign each a different number value. 0:18 Once created, use the variable names to add the variables together, and 0:21 then print this outcome to the console. 0:25 Pause here and give it a try. 0:29 If you weren't able to figure it out, don't worry, we'll try it together. 0:33 Before we write any new code, let's use the clear command to clean up the console. 0:38 That's the word clear followed by parentheses. 0:43 First, let's create a variable named number1 and set it equal to 100. 0:48 Now, we'll set a variable name number2 to 150. 0:59 Next, we'll combine them using the plus sign or 1:12 addition operator by typing number1 + number2. 1:16 Now when you press Enter, you'll see the result of this equation. 1:23 You can even see a preview before. 1:28 Nice work. 1:31 What do you think might happen if we try adding two strings together? 1:32 Try typing "hello" + "fsjs" and press Enter. 1:36 We get a combination of the strings without any spaces. 1:49 Other data types aren't allowed to do math, but 1:53 they come with their own operations. 1:55 For instance, when it comes to strings, the plus sign is referred to as 1:58 a concatenation operator and is used to combine two or more string values. 2:02 Let's try combining variables that store our first and 2:08 last names to print our full names. 2:11 We'll clear the console again, and I will create a variable named firstName, 2:12 Make sure it's a string, And a variable named lastName, 2:23 And combine those variables. 2:38 And uh-oh, again, we get our names together without a space between. 2:45 Concatenation works with exactly what we give it. 2:51 Let's add a space between the two names by using one more concatenation operator and 2:54 wrapping a space in quotation marks. 3:00 There we go, well done. 3:13 I've added a link to resources on concatenation and 3:16 strings to the teacher's notes. 3:19 I'll always encourage you to check the teacher's notes for helpful links that can 3:21 further your understanding of the concept we're learning. 3:25 You've gotten a glimpse of the power JavaScript gives developers to take input, 3:28 compute data, and provide output. 3:33 We've only scratched the surface. 3:36 Speaking of a surface, in the next video, 3:38 we'll have some fun making changes to the presentation layer of a web page with 3:41 JavaScript, just like a front-end developer does on the job. 3:45

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