Hi Idrees,
HANA is not merely a database, it is also an appliance
You need to separately buy HANA appliance
HANA stores all the data in RAM, uses parallel processing and also has an inbuilt light weight application server
If you want to try out HANA, then you can try 30 day trial at CloudShare, more info can be found in the link shared by Jon above
To start with HANA, you can refer to below blog:
Want to learn SAP HANA?Where to Start?Certification?
Regards,
Vivek