In the most basic terms, microcontrollers (MC) are small computers used on a single integrated circuit that are programmed by humans to do specific tasks. They typically contain a processor core, memory, and programmable input/output peripherals. They are designed for embedded applications, rather than in microprocessors (MP) which are used for personal computers, or other general purpose applications. MCs are located in devices like refrigerators, TVs, microwaves, printers and telephones. A Italian man named Massimo Banzi invented the Arduino, a hugely popular MC that has been a huge factor in the explosion of an international Maker Movement. Arduinos will be discussed in more detail in another tab.
In 1939, Vacuum Tubes were invented by John Ambrose Fleming.
In 1947, Transistor was invented by Bell Telephone Laboratories. This did everything the vacuum tube did but on a smaller scale, cheaper and more efficient.
(First Transistor) 
(Transistor Today)
In 1960, the Logic Gate was invented by Nicola Tesla which took even smaller amount of space.
In 1971, the Microprocessors was developed by Intel, and then the Microcontroller was developed by Texas Instruments.
Coding for MCs is performed on a computer in an Integrated Development Environment (IDE). Examples of programming languages include C++, Python, R, Arduino). The IDE debugs code errors, then compiles it into binary code (1s and 0s) which the MC executes. A programmer (a hardware, not a person) is used to transfer code from PC to MC. The most common programmer is an In-Circuit Serial Programmer (ICSP).
Application --> MPs are used for general computing (i.e. laptop, tablet, cell phone) while MCs are used in appliances, and specialized devices that focuses on constantly doing one thing.
Speed --> MPs have very fast processor speeds ( i.e. 2Ghz, 3Ghz) while MCs are relatively slow processor speeds.
External Parts --> MPs have many parts which include memory (RAM), storage space (hard drive) and imaging. MCs have few and work as a stand alone device where everything is typically built into it.
Costs --> MPs tend to be more expensive, very complicated and high tech manufacturing processes, while MCs are cheaper because they have simpler processes.
Energy Use --> MP have a medium to high energy use, while MC are very low to low energy use.
Vendors --> MPs are made by companies like Intel, AMD, ARM, while MCs are made by companies like Atmel, ST, Texas Instruments, and Microchip.
