|MadSci Network: Physics|
Wow, that's a tall order. To list the advancements even in the last five years would be a challenge. Twenty years is an eternity technologically speaking. Even restricting it to information and communication technology doesn't help much, because those fields are among those that have grown the fastest. In fact, some "advancements" of the last 20 years are already obsolete. But I'll try.
The most obvious advancement in both topics is the growth of the Internet. In 1980, the ARPANet interconnected several hundred university, corporate and government sites. The total number of users was in the range of several thousand or ten thousands, depending on how you define a user. The present Internet is growing at an exponential rate and as of March, 2000 one survey estimated the world total of Internet users at over 300 million.
The present-day Internet would not exist without advancements in computers since 1980; that was the year Seagate released the first hard disk drive for microcomputers--it held 5 megabytes and weighed about two pounds. The laptop computer on which I am typing this response has a removable hard drive which weighs 6 ounces and holds 5 gigabytes of data. That's an increase in information density vs. weight by a factor of 4000. The increase in speed of computers has also changed substantially. In 1981, the newly-released IBM-PC used an Intel processor running at 4.77 MHz. My laptop's Pentium II processor runs at 300 MHz, and is considered a slower, older model.
Hand in hand with computing advancements is the revolution in personal communication. In 1980, most businesses and essentially all households in the world had only POTS ("Plain-Old Telephone Service"). About the most sophisticated consumer accessory for your home phone was an answering machine. Nowadays, it's very rare to find a POTS-only phone as extra features and functionality are practically given away by competing service providers. Add to that the explosion in cellular systems in the last 10 years and it's clear that communication has truly seen a sea-change.
I don't know how much more detail to give you. So much has happened that it's probably useful for you to do a little research of your own:
History of Computers:
History of Communication
There is also an excellent book on the history of telecommunication by science fiction and fact writer Arthur C. Clarke, which you might be able to find in your local library:
"How the World Was One: Beyond the Global Village" (1992) Arthur C. Clarke
Hope this helps,
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