Updated README.md (#37)

* Fixed grammatical error

* Fixed grammatical error

* Fixed some grammatical errors

* Updated README.md

* Updated README.md

* Updated README.md

Updated the changes according to the reviews

* Update README.md

Co-authored-by: Jim Bennett <jim.bennett@microsoft.com>

1-getting-started/lessons/1-introduction-to-iot/README.md

@@ -22,11 +22,11 @@ In this lesson we'll cover:
 
 ## What is the 'Internet of Things'?
 
-The term 'Internet of Things' was coined by [Kevin Ashton](https://wikipedia.org/wiki/Kevin_Ashton) in 1999 to refer to connecting the Internet to the physical world via sensors. Since then the term has been used to describe any device that interacts with the physical world around it either by gathering data from sensors, or providing real-world interactions via actuators (devices that do something like turn on a switch or light an LED), generally connected to other devices or the Internet.
+The term 'Internet of Things' was coined by [Kevin Ashton](https://wikipedia.org/wiki/Kevin_Ashton) in 1999, to refer to connecting the Internet to the physical world via sensors. Since then, the term has been used to describe any device that interacts with the physical world around it, either by gathering data from sensors, or providing real-world interactions via actuators (devices that do something like turn on a switch or light an LED), generally connected to other devices or the Internet.
 
 > **Sensors** gather information from the world, such as measuring speed, temperature or location.
 >
-> **Actuators** convert electrical signals into real-world interactions such as levers, turning on lights, making sounds, or sending control signals to other hardware such as to turn on a power socket
+> **Actuators** convert electrical signals into real-world interactions such as triggering a switch, turning on lights, making sounds, or sending control signals to other hardware, for example to turn on a power socket.
 
 IoT as a technology area is more than just devices - it includes cloud based services that can process the sensor data, or send requests to actuators connected to IoT devices. It also includes devices that don't have or don't need Internet connectivity, often referred to as edge devices. These are devices that can process and respond to sensor data themselves, usually using AI models trained in the cloud.
 
@@ -34,19 +34,19 @@ IoT is a fast growing technology field. It is estimated that by the end of 2020,
 
 ![A graph showing active IoT devices over time, with an upward trend from under 5 billion in 2015 to over 30 billion in 2025](../../../images/connected-iot-devices.svg)
 
-✅ Do a little research: how much of the data generated by IoT devices is actually used, and how much is wasted? Why is so much data ignored?
+✅ Do a little research: How much of the data generated by IoT devices is actually used, and how much is wasted? Why is so much data ignored?
 
-This data is the key to IoT's success. To be a successful IoT developer, you need to understand the data you need to gather, how to gather it, how to make decisions based off it, and how to use those decisions to interact back with the physical world if needed.
+This data is the key to IoT's success. To be a successful IoT developer, you need to understand the data you need to gather, how to gather it, how to make decisions based on it, and how to use those decisions to interact with the physical world if needed.
 
 ## IoT devices
 
 The **T** in IoT stands for **Things** - devices that interact with the physical world around them either by gathering data from sensors, or providing real-world interactions via actuators.
 
-Devices for production or commercial use, such as the consumer fitness trackers, or industrial machine controllers, are usually custom made. They use custom circuit boards, maybe even custom processors, designed to meet the needs of a particular task, whether that's being small enough to fit on a wrist, or rugged enough to work in a high temperature, high stress, high vibration factory environment.
+Devices for production or commercial use, such as consumer fitness trackers, or industrial machine controllers, are usually custom-made. They use custom circuit boards, maybe even custom processors, designed to meet the needs of a particular task, whether that's being small enough to fit on a wrist, or rugged enough to work in a high temperature, high stress or high vibration factory environment.
 
-As a developer, either learning about IoT or creating a prototype device, you'll need to start with a developer kit. These are general purpose IoT devices designed for developers to use, often with features that you wouldn't see on a production device, such as a set of external pins to connect sensors or actuators to, hardware to support debugging, or additional resources that would add unnecessary cost when doing a large manufacturing run.
+As a developer either learning about IoT or creating a device prototype, you'll need to start with a developer kit. These are general-purpose IoT devices designed for developers to use, often with features that you wouldn't see on a production device, such as a set of external pins to connect sensors or actuators to, hardware to support debugging, or additional resources that would add unnecessary cost when doing a large manufacturing run.
 
-These developer kits usually fall into two categories - microcontrollers and single-board computers. These will be introduced here, and we'll go into them in more detail in the next lesson.
+These developer kits usually fall into two categories - microcontrollers and single-board computers. These will be introduced here, and we'll go into more detail in the next lesson.
 
 > 💁 Your phone can also be considered to be a general-purpose IoT device, with sensors and actuators built in, with different apps using the sensors and actuators in different ways with different cloud services. You can even find some IoT tutorials that use a phone app as an IoT device.
 
@@ -56,19 +56,19 @@ A microcontroller (also referred to as an MCU, short for microcontroller unit) i
 
 🧠 One or more central processing units (CPUs) - the 'brain' of the microcontroller that runs your program
 
-💾 Memory (RAM and program memory) - where your program, data, and variables are stored
+💾 Memory (RAM and program memory) - where your program, data and variables are stored
 
-🔌 Programmable input/output (I/O) connections - to talk to external peripherals (connected devices) such as sensors or actuators
+🔌 Programmable input/output (I/O) connections - to talk to external peripherals (connected devices) such as sensors and actuators
 
-Microcontrollers are typically low cost computing devices, with average prices for the ones used in custom hardware dropping to around US$0.50, with some devices as cheap as US$0.03. Developer kits can start as low as US$4, with costs rising as you add more features. The [Wio Terminal](https://www.seeedstudio.com/Wio-Terminal-p-4509.html), a microcontroller developer kit from [Seeed studios](https://www.seeedstudio.com) that has sensors, actuators, WiFi and a screen costs around US$30.
+Microcontrollers are typically low cost computing devices, with average prices for the ones used in custom hardware dropping to around US$0.50, and some devices as cheap as US$0.03. Developer kits can start as low as US$4, with costs rising as you add more features. The [Wio Terminal](https://www.seeedstudio.com/Wio-Terminal-p-4509.html), a microcontroller developer kit from [Seeed studios](https://www.seeedstudio.com) that has sensors, actuators, WiFi and a screen costs around US$30.
 
 ![A Wio Terminal](../../../images/wio-terminal.png)
 
-> 💁 When searching the Internet for microcontrollers be observant of searching for the term **MCU** as this will bring back a lot of results for the Marvel Cinematic Universe, not microcontrollers.
+> 💁 When searching the Internet for microcontrollers, be wary of searching for the term **MCU** as this will bring back a lot of results for the Marvel Cinematic Universe, not microcontrollers.
 
 Microcontrollers are designed to be programmed to do a limited number of very specific tasks, rather than being general-purpose computers like PCs or Macs. Except for very specific scenarios, you can't connect a monitor, keyboard and mouse and use them for general purpose tasks.
 
-Microcontroller developer kits usually come with additional sensors and actuators on board. Most boards will have one or more LEDs you can program, along with other devices such as standard plugs for adding more sensors or actuators using various manufacturers ecosystems or built in sensors (usually the most popular ones such as temperature). Some microcontrollers have built in wireless connectivity such as Bluetooth or WiFi, or have additional microcontrollers on the board to add this connectivity.
+Microcontroller developer kits usually come with additional sensors and actuators on board. Most boards will have one or more LEDs you can program, along with other devices such as standard plugs for adding more sensors or actuators using various manufacturers' ecosystems, or built in sensors (usually the most popular ones such as temperature sensors). Some microcontrollers have built in wireless connectivity such as Bluetooth or WiFi, or have additional microcontrollers on the board to add this connectivity.
 
 > 💁 Microcontrollers are usually programmed in C/C++.