RAM is operative memory. It is place where the information for the software working at the moment is kept and it gives access to the software. RAM memory is built by cells, which contain condenser and transistor. The condenser that is loaded with electricity indicates byte with value one and the rarefied condenser indicates byte with value zero. The processor supports the condenser with value one loaded with electricity. All the renovations are made with frequency one million times per second. When the system is off and the processor does not work, all the information in RAM is being deleted. So when you are loading multiple programs on your laptop, the operative memory is filled up and your laptop starts using the hard disk.
Is actually more RAM equal to faster computer? It is not obligatory. If you do not load up your computer with too much software opened for use, you can hardly see the difference between gigabytes. There will be no difference between four gigabytes and six gigabytes. But if you are loading up your computer with tens of software opened and want to use it at 100% it is good idea to upgrade your RAM. Because of the fact that we often use at the same time mail software and music player and text editor and internet explorer and anything else upgrading is good idea. We are not used to open only one program at a time. This needs enough RAM. At the same time when we are working long time with our laptop, it detaches some additional inactive memory, which keeps information from the unused at the moment software, which are at stand by regime. So with this the RAM decreases even more.
Of course everything depends on what work you want to do with your laptop. If it is for basic things the RAM is not that important. But if your aim is working with heavy software like architecture or design software you will need the RAM to be the highest. Three gigabytes are enough for watching movie, listening to music, surfing in internet, writing and drawing. For playing games you will need at least four gigabytes for the old games and about six gigabytes for the new games. Well actually if you have some extra money to invest, believe me additional RAM memory is never unduly.