The Basics

TypeScript programs are made up of a series of instructions called statements. These instructions are read by the computer (the browser) from the top to the bottom and from left to right.

In many TypeScript programs, you will see that each statement ends with a semicolon (;). While not necessary, some teams will use this style. At SDG, we follow a style where the semicolons are not required. We recommend you use an automatic code formatter named Prettier which will ensure proper style.

Each line of code represents a single idea. Even though our computers seem smart, computers are simple machines that only understand 1 very simple command at a time. The advantage that computers have over people is that they run those simple commands really fast.

Most of what we do when we write code is one of two actions: storing data or manipulating data. Let's start with storing data.

Comments

When writing code, we can leave comments to document the code. This helps remind the author, or other readers, of the purpose of the code.

Comments look like this:

// This is a single line comment
/* This is a longer comment
that spans multiple lines
*/

Comments behave like whitespace and are discarded during script execution.