Primary storage allows for the short-term storage of data. Information is retained for immediate use and is directly accessible by the CPU, usually until the main device is reset or turned off. The primary memory of a computer is called random access memory or RAM, with the two most commonly used forms of modern RAM being static RAM (SRAM) and dynamic RAM (DRAM). The global DRAM market is projected to reach 84 billion U.S. dollars by 2025 and, for the time being, the largest manufacturer of DRAM in terms of revenues is Samsung.
Secondary storage, either in the form of hard drives (HDD), solid states drives (SSD), flash drives, or other longer-term storage devices, record and hold data indefinitely, even when the main device is unpowered. In 2016, over 425 million HDD units were shipped, while worldwide shipments of SSDs were on track to exceed 160 million units in 2017.
In addition to local data storage, there is a growing demand for data storage that is portable and not reliant on local storage capacity. One technology fulfilling this need is cloud storage, hosted services delivered over the internet. With over 2 billion forecasted cloud users worldwide by 2020, such services enable users and enterprises to store data in third-party data centers, which can then be accessed without building additional data storage into a particular device. Some of the most popular cloud storage service providers among small businesses in the United States include: Dropbox, Google Drive, Apple iCloud and Microsoft OneDrive.
Finally, not all data needs to be immediately accessible. Some requires secure, long-term storage solutions, whether for regulatory reasons or due to the value that the data can provide through content analysis at a later date. This market for information archival is growing along with the rest of the data storage market. As at 2015, the global market for information archiving was worth an estimated 4.3 billion U.S. dollars and is projected to be worth about 7.2 billion U.S. dollars by 2021.