You will come across two kinds of memory, primary memory, and secondary memory. Primary memory has got limited storage capacity & is quite volatile. But, secondary memory overcomes such limitations by offering permanent data storage and in quantity. In this post, we will look in detail at the second type of memory that is secondary memory.Secondary memory is termed external memory and mainly refers to different storage media where the computer will store its data & programs. Secondary storage media is either fixed or removable. The Fixed Storage media can be an internal storage form like a hard disk, which is fixed in the computer. The storage medium is portable and easy to take outside the system will be called a removable storage form.What is Secondary Memory?Secondary memory is one type of computer memory, which is persistent and non-volatile & isn’t directly accessed by your computer or processor. This allows users to store enough data that can be easily and instantly retrieved, transported as well as used by the services and applications. The secondary memory is called secondary storage.Features of the Secondary Memory:Given are a few important characteristics of the secondary memory that differentiate it from the primary memory.Non-volatile and retains your data when you switch off the powerLarge capacities to tune of terabytesCheaper compared to the primary memoryTypes of Secondary MemoryNo matter if secondary memory is a part of your CPU or not, but there are 2 kinds of secondary memory –removable and fixed.Solid-State Drive (SSD)SSD makes use of a simple memory chip named NAND flash memory, it is the newer type of storage device that is used in computers and replaces HDDs. SSDs can speed up the computer that can improve its performance.NAND flash has got transistors that will conduct current & set value to 1, when it does not, then the value is set to 0. With this, SDD can store enough data at a very high speed.Hard DiskThis is one rigid magnetic disc used for storing data. Hard disk permanently stores your data as well as is located in the drive unit. It is a fixed memory type. A hard disk is a rigid magnetic disc, which stores your data permanently since it is a non-volatile device.Hard disk is mainly located within your computer’s motherboard & it includes platters packed in the air-sealed casing. Data is written over the platters just by moving the magnetic head on the platters when they spin. Data stored on the computer’s hard drive normally includes an operating system, user’s files & programs, installed software, pictures, text documents, music, videos, and more.CD DriveCompact Disk is also called circular disks and mainly uses optical rays, generally, lasers, to read & write data. They’re cheap since you may get 700MB of the storage space for just one dollar or less. CDs can be inserted in the CD drives that are built in your CPU cabinet. They’re portable, remove the CD & carry them with you. There’re three kinds of CDs.CD-ROM− Data can be recorded by the manufacturer on these CDs. The proprietary software, video, and audio can be released on the CD-ROMs.CD-R− The user can write data once on a CD-R and cannot get deleted and modified later.CD-RW – Easy to write and delete data on these disks again & again.SD CardSecure Digital Card or SD Card is mainly used in portable & mobile devices like smartphones & digital cameras. You may remove this from your device as well as see things stored using the computer with a card reader.There’re several memory chips built inside an SD card that helps to store data; it doesn’t have several moving parts. The SD cards aren’t made equal, hence they might differ from one another in the terms of physical sizes, speed, and capacity. For instance, standard SD cards, micro, and mini SD cards.Network-Attached Storage (NAS)NAS is another type of storage network, basically, it is the specialized file server. What is very good about NAS is it has plenty of space & if you have a proper ethernet connection, you can get access.Although NAS isn’t very good for databases since it isn’t very fast, it is cheap which makes it the best choice to start. This storage network supports high-end applications like rendering & 3D animation, and analytics!Digital Video Display or DVDDVDs have a higher storage capacity compared to CDs. Furthermore, they even store multimedia files, which need very high storage space. Also, the storage capacity of DVD ranges between 4.7GB – 17GB. Besides, we call it a digital versatile disk. They are available in three different types:Floppy DiskThey are small removable disks with magnetic recording material. The floppy disks are 3.5 inches in diameter and will hold over 1.44MB of data. It is a portable storage device that is rewritable media & reused several times. The floppy disks are mainly used to move various files between your computers. The primary disadvantage of the floppy disks is they can easily be damaged and, thus, aren’t much reliable.Blu Ray DiskBlu-ray disk or BD makes use of the optical rays to store data. This has an amazing storage capacity of over 54 GB. Thus, it can also store HD videos or other multimedia. It makes use of blue rays that are of the shorter wavelength that allows higher data storage.How to Store a Huge Amount of Data?Suppose you are not having enough storage space on the devices, then it is the time you must look at the alternative storage device. External storage devices like flash drives may run out of space, can break, and even get lost. For this reason, the best method to store your data and files is in the cloud. It is much safer, faster, as well as simple to access.