Solid State Drive (SSD) is the next generation data devices that use microchips to store data, and are designed to allow access to data in the same way as a traditional Hard drive (HDD). The HDD has spinning disks and movable read/write heads, whereas there are no movable parts in an SSD, since data is stored on microchips. Since the interface is the same as a normal HDD, the SSDs can easily slot in where the HDD was.

Advantages of an SSD
The three biggest advantages of an SSD in comparison to an HDD are as follows.

1. No spin up time:     Conventional HDDs need to spin up, and that takes time. Even though that is only a few seconds, that feels like a lot when compared to the milliseconds it takes for an SSD to be ready for action – from the low power state. There is no spin-up of a mechanical part in an SSD.
What this means for you: The OS will load up faster, and in case the PC is on standby/sleep mode, it will be ready for access sooner.

2.Random access time & Read latency time: Conventional HDDs take 5ms-10ms, since it takes some time for the physical parts to spin up. An SSD, for the lack of any moving parts, has an access time of about 0.1ms. 
What this means for you: Applications will open faster, data access during operation will be quicker, and for the gamers – gaming performance of the Notebook will witness a huge improvement.

3. No defragmentation: SSDs don’t suffer data defragmentation, since flash memory reads and writes data sequentially. HDDs tend to end with fragments of large files, of a lot of data has been copied to and fro from the drive, or
What this means for you: One less maintenance thing for you to do!

 Apart from these three, there are some more.

An SSD has literally no moving parts. Means that it is less susceptible to mechanical failures.
Carrying on from the previous point, it also means that an SSD performs in a much more silent fashion.
Weight is an important criterion particularly if you plan on installing an SSD in a portable PC. An SSD has a huge advantage here.

Should you buy an SSD?
Well, that is the big question, isn't it? The simple point is that SSD are expensive. For the amount of money (Rs 5500) that gets you a Corsair 40GB SSD, you can get a 1TB 2.5-inch HDD.

There are a handful of reasons why you should get an SSD-
1. The performance increase is significant, since the read speeds are a lot more than an HDD. However, lower end SSDs do cut down on the write speeds – takes away some bit of the performance advantage. If you are buying a mid range version, both read as well as write speeds are pretty much equal. The critical element here is to not buy the very basic SSD. If that calls for increasing your budget, or waiting for a while to do that, we suggest you walk the path of patience.
2. The other scenario is that you are using it on a PC, and using the SSD for installing the OS, and a standard HDD for storing data. In this case, you can get a 40GB SSD, and just keep the OS installed on it. However, not too many programs can be loaded on this.
3. You want to install an SSD on a laptop, and either you don’t keep any data on the drive, or use an external drive for that. In that case, even a generally sluggish machine will feel very zippy. At least a 80GB for this scenario, since you don’t have a secondary internal drive here in case you need one in the future.