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Information Technology/ITS TIME FOR A CHANGE 2


(This is not a spam question or a homework question)
I was wondering would you please explain to me in a simple way that I can understand: how does the mac computer clock actually change by it self?


Hello Cameron,
To be sure I can answer your question well, I'd like to know a little more about what you actually want to know. Are you specifically talking about a Mac or any computer? If you are talking about a computer clock and how it works, this is it in a nutshell;
There is a counter for the current moment on the main board, let's say it reads "000000". A chip on the main board fires a signal that increases that number by 1. This happens about 18.2 per second, so very fast. This means that when the counter reads 000018, about one second has passed. This goes on forever, as long as there is electricity to make the clock 'tick'. Even when a computer is off, and even without it being plugged in to a power socket, a battery will make sure it keeps ticking. Whenever a program on the computer neads to read the time, it uses this number. Computers are set to think about a starting point (the 000000) and usually they take 1 January 1900. As it can keep track of time for years, and it counts 1 point in every 18th part of a second, you will understand the counter will have many digits, something like 00000000000000000000000000000000000000000. But that's not a problem for a computer. It computes the exact date and time based on this number by taking 1 January 1900 and adding all those pieces of seconds. This can be done so fast that you just notice the current minute, or the second if you show the seconds hand. It can display this on your screen so you can know what time it is.
These days, computers can also use the internet to check the current time. They set the counter based on a question they ask to internet servers about the exact time. These internet servers in turn get their time from a super computer that uses an 'atomic clock', a clock that ticks based on an piece of nuclear material that gives out a 'signal' EXACTLY every so many parts of a second. It is very accurate.

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Philip Lafeber


I have been specialising in knowledge analysis and modelling. I have an interest in the way models of programs, architectures, business processes and the like are properly made and analysed. What`s meant by `properly` depends on the goal you`re trying to achieve. The analysis of this goal and the way it can best be realised is something you might want to ask me about.


I have studied knowledge modelling and analysis, worked in building information systems using Oracle at Canon, and consulted about information management setup for various customers at Mavim. I have also built databases in MS Access.

Master in Artificial Intelligence at University of Amsterdam, 2 courses in Oracle Portal, de facto Mavim certified consultant, 2 courses in Government Enterprise Architecture by IIR and Novius, Itil foundation.

Past/Present Clients
University of Amsterdam, Bolesian, Canon europa, Solveware, NetlinQ

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