in this video, we'll examine the different elements which constitute a computer from the most external components you all know - the most internal which allow it to work so here is a classic computer here we have the big box we call the computer system unit a monitor a keyboard a mouse in an external hard drive these last components called external peripheral devices input devices like the keyboard the mouse or a camera or a scanner they can also be output devices like a monitor or a printer input-output devices like the external hard drive with which we can read the information at the input and write information at the output all these external peripheral devices are plugged into the back of the computer into sockets named ports I've turned the computer around and you can see here all the connections made at the back of the computer system unit most of these connections are provided by socket, called ports here we can see USB ports for the external hard drive but also for the mouse here a picosecond slash 2 port for the keyboard DVI ports to which the monitor is plugged there are also other ports like the firewire ports and here a specific port an Ethernet port which demonstrates that the Internet can also, be seen as a peripheral device external to the computer now let's look at what happens inside the computer system unit there are many things inside this computer system unit but let's begin with the connection to the outside here we have the power supply which is plugged into this power supply unit all the cables of a certain color will carry electricity opponents of the computer the monitor here is plugged into this this element which is the video card at last, the other elements the keyboard, the mouse, and the drive are plunged into this big plate we see at the bottom that is called the motherboard the different elements here are the power supply the video card in the motherboard at the bottom other elements here we have a DVD player burner drive and a floppy disk drive and we can see they're powered and here we have two hard drives actually, these different elements are like peripheral devices but internal this time we can see they are powered and this blue cable here or this gray ribbon here connect them to the motherboard thanks to internal ports this time to better see the computer core I will also remove this big block here which consists of a fan of a cooling system for the central processing unit CPU so I've removed the DVD burner and the floppy disk drives as well as the power supply the big cooling block here I can remove it you can see the CPU below and the remaining element is a fan I've also removed the two hard drives I've kept one to show you that it's connected to the motherboard with a port there's more we can see the motherboard a little better but there are still circuits I've already talked about some of them here the video card and here a card with which the firewire ports can be controlled which are still not part of the computer core and here are the essential elements of a computer with hard drives which are the massed storage but I can remove them here we have printed circuit board which I can also remove it's the random access memory the RAM that's it we've removed all the internal peripheral devices and there are two elements left here is the motherboard and in particular little electronic circuits here with which the different ports we could see from outside are managed they're called controllers and finally, the only element that really matters is this here the CPU here is the heart of the computer I opened the protection cover and I can remove the CPU we can see here it's connected to the motherboard numerous little legs that act like ports the CPU is the essential computing unit of the computer even inside the CPU we will find a specific design with memory areas named caches and several computer units usually, many which work simultaneously to be more efficient i zoom out on the computer now we can see the central element that is the link between all the other elements of the computer it's the motherboard the motherboard is the computer main circuit board it its a thin plate that holds the CPU the fundamental element which communicates via the motherboard with internal peripheral devices such as RAM or hard drives the video card the DVD burner drive but also with external devices through port controllers which can be seen at the back of the computer