Cloud computing is the delivery of computing as a service rather than a product, whereby shared resources, software, and information are provided to computers an d other devices as a utility (like the electricity grid) over a network (typically the Internet) .Cloud computing provides computation, software, data access, and storage services that do not re quire end-user knowledge of the physical location and configuration of the system that delivers the servi ces.It is a byproduct and consequence of the ease-of-access to remote computing sites provided by the Internet.This may take the form of web-based tools or applications that users can access and use throug h a web browser as if the programs were installed locally on their own computers.Most cloud computing infrastructures consist of services delivered through shared data-centers and appearing as a single poin t of access for consumers computing needs. Commercial offerings may be required to meet service-level agre ements (SLAs), but specific terms are less often negotiated by smaller companies. Characteristics : 1] Agility : improves with users' ability to re-provision technological infrastr ucture resources. 2] Application programming interface (API) : accessibility to software that enab les machines to interact with cloud software in the same way the user interface facilitates inte raction between humans and computers. Cloud computing systems typically use REST-based APIs. 3] Cost : is claimed to be reduced and in a public cloud delivery model capital expenditure is converted to operational expenditure. 4] Reliability : is improved if multiple redundant sites are used, which makes w ell-designed cloud computing suitable for business continuity and disaster recovery. 5] Performance : is monitored, and consistent and loosely coupled architectures are constructed using web services as the system interface. 6] Security : could improve due to centralization of data, increased security-fo cused resources. 7] Maintenance : of cloud computing applications is easier, because they do not need to be installed on each user's computer. Advantages : not just while in the office. 1] Access your data at all times 2] A physical storage center is no longer needed. 3] Most have a pay structure that only calls for payment only when used. 4] Relieves burden on IT Professionals and frees up their time in the office. 5] Easily scalable so companies can add or subtract storage based on their own n eeds. 6] You receive secure, managed hosting at very inexpensive costs. 7] If something does goes wrong, you can get the support of your service provide rs.
Disadvantages : 1] Lost control comes with handing over your data and information. 2] Depends on third-party to ensure the security and confidentiality of data and information. 3] You do not have control over the remote servers, their software, or their sec urity. 4] It may be difficult (or even impossible) to migrate massive amounts of data f rom the provider.