Defrag-anitvirus-Firewall

Defragmentation

defragmentation is when you take your computers storage or memory and place it all in an organised order.
when files have been added to a computer they get stored in multiple places. when you go and delete these files it leaves lots of gaps in different areas of the computer. and say you wanted to add a new software to your computer then it would have to spread out all the information between all the different gaps that was left. this is a problem because when we want to run the new software we will find it will be very slow this is because it has to look for the information in lots of different places which takes a lot of time.

defragmentation is what you do to your computer in which they take all the information group it together correctly then organize them. it is important to defrag your computer at least once a year or if you feel you've been installing a lot or deleting a lot of files.

Anti-virus

an anti-virus stops viruses from getting into your computer, simple as that. the way antivirus works is that it runs in the background of the computer, and as it is on it will look through all files and scan your entire computer looking for any known viruses. your anti virus also makes sure that before you open any new files that it scans them to make sure they don't hold any threats, it also does the same from documents downloaded from the internet.

you can manually set your computer to scan for viruses but if you have installed an antivirus on your computer then it means it will normally run itself in the background as you are working.

Firewall

a firewall works similar to anitvirus except it checks for viruses from the internet - before they've gotten into your computer. firewalls also help against hackers getting into your computer too, they serve as a sheild to your computer. the firewall is said to be like a barrier for your computer. it has different methods of scanning the information from the internet and from that it will decide whether the information should be let in or not. an example of how firewall asses' information is through packet filtering. packet filtering is when small packets of data are scanned by the fire wall then decided whether to be rejected or allowed into the computer. its important to have a firewall and an antivirus protecting your computer.

relative and absolute cell referencing.

Absolute cell referencing

absolute cell referencing is mainly used when you're on excel. Absolute cell referencing is when you use a cell in a formula, and if you copy, move or duplicate the formula then these cells will never change. you make a cell in a formula into absolute referencing by adding dollar signs. if you put a dollar sign in front of the letter then the cell reference will make sure that it stays in that column. if you put a dollar sign in front of the number then it will keep that row. by putting dollar signs in front of both the letter and the number it means that we reference that one cell, and only that cell.

we can use absolute cell referencing when we want to use a formula and we want it to always refer back to that cell. a good use of this would be if we had to see whether a set of number is equal to a specified number. say we have a set of 10 random numbers and we want it to say 'match' if the random number and the specified number are the same. for this we could use one formula for the first number and absolute cell reference the specified number. we can then use this formula for each of the numbers and they should all accordingly change but not the absolute referenced cell.

Relative cell referencing

Relative cell referencing is the opposite to absolute cell referencing. if you have a formula in a cell and you try to move, change or duplicate the formula then all the cells will change accordingly in the cell. if we want to do the formula =B2+C2 and we put this formula in D2, then it would simply show us the right outcome. if we then copied this formula and put it into cell D3 then we would find that the formula will change to =B3+C3. this can come in handy when working with a mass of cells.

Old school IT

so today i made a timeline on old school IT

heres a link to the pretty web site 

https://www.timetoast.com/timelines/1168789

so now for the question that caused me to look at all this old school stuff. 

describe 2 disadvantages of delivering a presentation using printed acetate.

and my answer to that dear friend is. 

1) if the light bulb is blown in the projector then it will not work and become useless. also it is very expensive to any broken equipment in these machines. 

2)you have to take into account the angles in which you put the acetates on. because you dont want them to show upside or with the words back to front. 

ta-dah and thats my answer. totally worth 4 points