Note that RAID level 0 is not categorized as fault tolerant. The fault tolerant levels to a different degree are 1, 5, 6 and 1+0. If a single hard drive in the array fails, there is still the reconstruction of data on the fly and the occurring of no access interruption. One can define RAID level 2, 3 and 4 theoretically but these are not practically used. You can find some other complex layouts. RAID 5E/5EE [integration of some spare space], RAID 50 and 60, which are a combination of RAID 5 or 6 with RAID 0 and RAID DP. Giving their reference here is beyond the scope.
Striping and Blocks
By striping, the data is stored on the risk array. This contagious data stream is broken into blocks and the blocks are further broken to various disks in a particular pattern. The use of striping is done with the RAID levels 0,5,6 and 10. You will choose the block size after the creation of array. The typical size of the blocks is from 32kb to 128kb. RAID recovery comparison chart is of importance in this area.
When you need the performance use RAID 0 but there is no importance of data here. In RAID 0, the data is divided into chunks and then these blocks are written to disks in turn. RAID 0 gives the speed improvement especially when it comes to write speed. There is even distribution of read and write requests across various disks in the array. RAID 1 Mirror provides the same improvement comprising of reads but not writes. So, if there is a request related to blocks 1, 2 and 3, you can read each block from own disk. Thus you can read the data three times fast than from one disk.
Note that RAID 0 provides no fault tolerance. When the disks in array fail, the complete array fails and there is loss of data. You will find solutions of RAID 0 cheap and RAID 0 uses complete disk capacity. If the controller of RAID 0 fails, you can do the RAID 0 recovery easily by the help of RAID 0 recovery software. Keep in mind that if there is failure of the disk, there is irreversible loss of data.
There is need of mirroring when you require trusted storage of comparative small capacity. Mirroring [RAID1] deposits two same copies of data on two hard drives. If one drive fails, you can read data from other drive. There is no usage of strips and blocks in mirroring. There can be amendments in read speed when it comes to certain implementations. Read requests are transmitted to two drives in turn. There has to be an increase in the speed by a factor of 2 like RAID 0.
Summary: You have multiple ways when it comes to the organization of data in RAID array. These methods are called as RAID levels. In different RAID levels, you find different speeds and properties of fault tolerance.