On the Windows computer, click one of these — the Microsoft Store version is the easiest:

在 Windows 电脑上，点下面任意一个 —— Microsoft Store 版本最简单：

Or open the official page and choose a download: arduino.cc/en/software

或者打开官方页面自己选一个下载：arduino.cc/en/software

1. 1
   Microsoft Store → press Install.  Installer (.exe) → open the downloaded file and click I Agree → Install, then Finish.
2. 1
   Microsoft Store → 点 Install（安装）。 安装包 (.exe) → 打开下载好的文件，点 I Agree（我同意）→ Install（安装），最后点 Finish（完成）。
3. 2
   Open Arduino IDE (it may take a minute the first time).
4. 2
   打开 Arduino IDE（第一次打开可能要等一会儿）。
5. 3
   Plug the board into the computer: the square (USB-B) end into the board, the flat (USB-A) end into the computer. A little green power light turns on.
6. 3
   把开发板插到电脑上：方头（USB-B）那端插进开发板，扁头（USB-A）那端插进电脑。一个小小的绿色电源灯会亮起来。
7. 4
   In Arduino IDE: Tools → Board → Arduino AVR Boards → Arduino Mega or Mega 2560. If it offers to install “Arduino AVR Boards”, click Install.
8. 4
   在 Arduino IDE 里：Tools → Board → Arduino AVR Boards → Arduino Mega or Mega 2560。如果它提示要安装 “Arduino AVR Boards”，就点 Install（安装）。
9. 5
   Tools → Port → pick the port that appeared (something like COM3).
10. 5
    Tools → Port → 选刚刚出现的那个端口（类似 COM3）。

// Experiment 1 — Blink
// Pin 13 has a tiny LED soldered onto the board.

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);   // get pin 13 ready to send power
}

void loop() {
  digitalWrite(LED_BUILTIN, HIGH); // LED ON  (HIGH = 5 volts)
  delay(1000);                     // wait 1000 ms = 1 second
  digitalWrite(LED_BUILTIN, LOW);  // LED OFF (LOW = 0 volts)
  delay(1000);                     // wait 1 second
}

1. 1
   In Arduino IDE, delete anything in the editor and type (or paste) the code above.
2. 1
   在 Arduino IDE 里，删掉编辑器里原有的内容，把上面的代码打上去（或粘贴进去）。
3. 2
   Click the round → Upload button (top-left). Wait for “Done uploading.”
4. 2
   点左上角圆形的 → Upload（上传）按钮，等到出现 “Done uploading.（上传完成）”。
5. 3
   Watch the board — the little LED blinks on for 1 second, off for 1 second. 🎉
6. 3
   看着开发板 —— 小 LED 会亮 1 秒、灭 1 秒地闪起来。🎉

// Experiment 4 — Smart night light
const int sensorPin = A0;   // the light sensor
const int ledPin    = 9;    // LED on a "~" pin

void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);       // open a line to the computer
}

void loop() {
  int light = analogRead(sensorPin);            // 0 = dark ... 1023 = bright
  int brightness = map(light, 0, 1023, 255, 0); // darker -> brighter LED
  analogWrite(ledPin, brightness);
  Serial.println(light);    // print the reading
  delay(50);
}

1. 1
   Upload the code, then open Tools → Serial Monitor and set it to 9600 baud (bottom-right).
2. 1
   上传代码，然后打开 Tools → Serial Monitor（串口监视器），把它设成 9600 baud（波特率）（在右下角）。
3. 2
   Cover the sensor with your hand — the number drops and the LED gets brighter.
4. 2
   用手盖住传感器 —— 数字会变小，LED 会变得更亮。
5. 3
   Shine a phone light on it — the number rises and the LED dims.
6. 3
   用手机的灯照它 —— 数字会变大，LED 会变暗。