3 Random Facts Related to Technology
In this day and age, computers can almost be found anywhere. From areas above the skies of the earth to an ordinary person’s bedroom. However, although plenty of people know how to operate a personal computer, most individuals do not know what happens under the hood of many technologies. So, I compiled a list of interesting facts related to technology to help you get started with learning more about how numerous technologies work.
Binary and ASCII
Most of us have learned to use the base 10 system, or counting from 0 to 9, to count. But unlike many of us, computers use the binary system to count. The binary system, also known as the base two system of counting, is a system of counting with only two digits, 0 and 1. One binary digit is called a bit and 8 binary digits is equal to a single byte. Moreover, computers represent 1s and 0s through tiny switches called transistors. To illustrate, a switch that is turned on can represent 1 while a switch turned off can represent 0s.
Using the base 10 system, number 985 can be divided into hundreds, tens, and ones. With 5 as the ones, 8 as the tens, and 9 as the hundreds. The places can be represented as a ten raised to a power of increasing numbers because each place has ten possible values. So, 9 is 10^2, 8 is 10^1, and 5 is 10^0. You can also say that 985 is 100 * 9 + 10 * 8 + 1 * 5. Similarly, the binary system uses a number raised to a power of increasing numbers to represent different values. But, it uses number two for each place instead of ten because it only has two possible values. So for example, 3 can be shown as 11 since each digit in the binary system can only either be 1 or 0. To clarify, 11 can be seen as 2^1 + 2^0, which is equal to 3. Here’s another example, 19 could also be seen as 10011 because 20+21+2^4 is equal to 19. Therefore, computers represent the number 19 by having the small switches be turned on or off based on the 10011 pattern. Lastly, letters can also be seen in computers because the letters were mapped to different numbers. The computers use a system called ASCII, which assigns each symbol and letters to different numbers. For example, yes is just 121 101 115, while NO! is 78 79 33. If we use the binary system, this can be interpreted as 01111001 01100101 01110011 and 01001110 01001111 00100001. ASCII was helpful in writing different characters. But, because ASCII was only limited to 8 bits or a single byte, meaning that it only has a few characters available, another system that can have 16 bits was introduced to include more characters. This system was called the Unicode.
The Internet
There are some things that you need before you can connect to the internet, such as an IP address. An IP address, also known as the Internet Protocol address, is an address that works like your mailbox. It helps a network know which computer should receive a specific information and where they should send that information to. Additionally, IP addresses are displayed as a unique 32-bit address that have four groups of 8-bit numbers separated by periods. However, the range of the numbers in the IP addresses are limited to 0 to 255. Therefore, a group would not have numbers above 255 or below 0. One problem that IP addresses have is the fact that it only has a limit of 4 billion addresses and there are more than 4 billion devices connected to the internet. So, a solution that people developed was to give unique private addresses to different devices then direct them to one single IP address. However, people realized that it is not a good long term solution. So, they also developed another solution. They increased the number of bits an IP address has from 32-bits to 128-bits and called it IPv6 addresses while the 32-bits ones were called IPv4 addresses. As a result, IPv6 addresses have 8 groups of 16-bit hexadecimal digits.
The IP addresses our computers have are assigned by something called a DHCP server or a Dynamic Host Configuration Protocol server. So, If IP addresses were either numbers or hexadecimal digits, then how do we visit sites such as google.com, youtube.com, facebook.com, and etc.? The DNS, or Domain Name System, serves as the translator responsible for converting IP addresses to easy to remember names. You could think of them as like a record of IP addresses and their translated names. However, there is no DNS record of everything on the internet and more of just small scale DNSs that are just combined by different services. Thus, DNSs are decentralized and can be found in numerous servers.
Another thing that you need in order to connect to the internet is an access point. Access points are the network that your devices connect to, such as the airport free wifi. As mentioned earlier, unique IP addresses are given to multiple devices and are directed to one single IP address. These single public IP addresses are given to routers, which allows different devices to share the same IP address. Many home networks have access points that already contain a router, a switch, a modem, and more combined in one device. Additionally, the router is responsible for receiving the information on the internet and sending it to the right device, and also receiving information from a specific device and sending it to the correct destination. Therefore, computers have an access point, dhcp server, and a dns server between them and the internet.
Lastly, the internet is really just networks from different places that are interconnected, thus, internet or interconnected networks. Hence, the internet is just a set of rules that allows different networks to connect and communicate to each other.
IP
So at this point, we know that the internet is just networks that are interconnected. However, it is very inefficient and costly if every network is directly connected with each other. So, people developed a solution to address that problem. Networks are actually connected to a router. The router decides where the information to go based on the IP where it should send it to. However, it sends it to the routers closest to the IP instead of directly sending it to that IP address. Furthermore, the router uses the information from a router table to decide where the information should go. Additionally, it has a set of rules to decide where to send it. For example, if it receives an IP address that starts with 1, they make different decisions whether this is 1 or not, so that they know where they should send it to. Not only do routers send the information to the closest IP address where they should send it to, but routers also need to send it to a route where there is not too much traffic. This is called “rerouting” to a different path. Lastly, the networks do not send the whole information but send it into multiple broken down pieces of the information because it is more efficient and more cost effective. For instance, if there was a problem that occurred while sending the data. The network does not need to resend the whole thing, but just the broken down piece that was not sent due to a problem. But, the IP is not responsible for checking whether or not the information was sent properly or completely, the TCP handles that responsibility.