What is a SSD(Solid State Disk)?

You would have heard recently about pc/laptops with  capabilities of processing and  booting 60 times faster than your  existing one, this is because of the use of the latest SSD Disks which replaces the Hard Disk Drives used to store data.An SSD is a Solid State Device used to store the data in its solid state memory which often consists of SRAM or DRAM which makes it faster to store data and retrive data.These SSD disks have many advantages some of them are:
1. Computers with SSD boot faster than the similar spec pc's with hard disk as no spin up is required.
2. Typically fast random access for reading – as there is no read/write head to move.
3. Reduced noise.
4. Lesser energy consumption
5. Heat generation is comparitively low.

Disadvantages:

1.It is too costly at the moment to afford for normal use
2.Due to its prices  it is not freely available
3.At present only SSD's with lower capacity are introduced