Big data primarily refers to data sets that are too large or complex to be dealt with by traditional data-processing application software. Data with many entries (rows) offer greater statistical power, while data with higher complexity (more attributes or columns) may lead to a higher false discovery rate. Though used sometimes loosely partly because of a lack of formal definition, the interpretation that seems to best describe big data is the one associated with large body of information that we could not comprehend when used only in smaller amounts.
Big data analysis challenges include capturing data, data storage, data analysis, search, sharing, transfer, visualization, querying, updating, information privacy, and data source. Big data was originally associated with three key concepts: volume, variety, and velocity. The analysis of big data presents challenges in sampling, and thus previously allowing for only observations and sampling. Thus a fourth concept, veracity, refers to the quality or insightfulness of the data. Without sufficient investment in expertise for big data veracity, then the volume and variety of data can produce costs and risks that exceed an organization's capacity to create and capture value from big data.
Current usage of the term big data tends to refer to the use of predictive analytics, user behavior analytics, or certain other advanced data analytics methods that extract value from big data, and seldom to a particular size of data set. "There is little doubt that the quantities of data now available are indeed large, but that's not the most relevant characteristic of this new data ecosystem." Analysis of data sets can find new correlations to "spot business trends, prevent diseases, combat crime and so on". Scientists, business executives, medical practitioners, advertising and governments alike regularly meet difficulties with large data-sets in areas including Internet searches, fintech, healthcare analytics, geographic information systems, urban informatics, and business informatics. Scientists encounter limitations in e-Science work, including meteorology, genomics, connectomics, complex physics simulations, biology, and environmental research.
The size and number of available data sets have grown rapidly as data is collected by devices such as mobile devices, cheap and numerous information-sensing Internet of things devices, aerial (remote sensing), software logs, cameras, microphones, radio-frequency identification (RFID) readers and wireless sensor networks. The world's technological per-capita capacity to store information has roughly doubled every 40 months since the 1980s; as of 2012, every day 2.5 exabytes (2.5×260 bytes) of data are generated. Based on an IDC report prediction, the global data volume was predicted to grow exponentially from 4.4 zettabytes to 44 zettabytes between 2013 and 2020. By 2025, IDC predicts there will be 163 zettabytes of data. According to IDC, global spending on big data and business analytics (BDA) solutions is estimated to reach $215.7 billion in 2021. While Statista report, the global big data market is forecasted to grow to $103 billion by 2027. In 2011 McKinsey & Company reported, if US healthcare were to use big data creatively and effectively to drive efficiency and quality, the sector could create more than $300 billion in value every year. In the developed economies of Europe, government administrators could save more than €100 billion ($149 billion) in operational efficiency improvements alone by using big data. And users of services enabled by personal-location data could capture $600 billion in consumer surplus. One question for large enterprises is determining who should own big-data initiatives that affect the entire organization.
Relational database management systems and desktop statistical software packages used to visualize data often have difficulty processing and analyzing big data. The processing and analysis of big data may require "massively parallel software running on tens, hundreds, or even thousands of servers". What qualifies as "big data" varies depending on the capabilities of those analyzing it and their tools. Furthermore, expanding capabilities make big data a moving target. "For some organizations, facing hundreds of gigabytes of data for the first time may trigger a need to reconsider data management options. For others, it may take tens or hundreds of terabytes before data size becomes a significant consideration."
Berkhamsted (/ˈbɜːrkəmstɛd/ BUR-kəm-sted) is a historic market town in Hertfordshire, England, in the Bulbourne valley, 26 miles (42 km) north-west of London. The town is a civil parish with a town council within the borough of Dacorum which is based in the neighbouring large new town of Hemel Hempstead. Berkhamsted, along with the adjoining village of Northchurch, is encircled by countryside, much of it in the Chiltern Hills which is an Area of Outstanding Natural Beauty (AONB).
The High Street is on a pre-Roman route known by its Saxon name: Akeman Street. The earliest written reference to Berkhamsted was in 970. The settlement was recorded as a burbium (ancient borough) in the Domesday Book in 1086. The most notable event in the town's history occurred in December 1066. After William the Conqueror defeated King Harold's Anglo-Saxon army at the Battle of Hastings, the Anglo-Saxon leadership surrendered to the Norman encampment at Berkhamsted. The event was recorded in the Anglo-Saxon Chronicle. From 1066 to 1495, Berkhamsted Castle was a favoured residence of royalty and notable historical figures, including King Henry II, Edward, the Black Prince, Thomas Becket and Geoffrey Chaucer. In the 13th and 14th centuries, the town was a wool trading town, with a thriving local market. The oldest-known extant jettied timber-framed building in Great Britain, built between 1277 and 1297, survives as a shop on the town's high street.
After the castle was abandoned in 1495, the town went into decline, losing its borough status in the second half of the 17th century. Colonel Daniel Axtell, captain of the Parliamentary Guard at the trial and execution of King Charles I in 1649, was among those born in Berkhamsted. Modern Berkhamsted began to expand after the canal and the railway were built in the 19th century. In the 21st century, Berkhamsted has evolved into an affluent commuter town.
The town's literary connections include the 17th-century hymnist and poet William Cowper, the 18th-century writer Maria Edgeworth and the 20th-century novelist Graham Greene. Arts institutions in the town include The Rex (a well regarded independent cinema) and the British Film Institute's BFI National Archive at King's Hill, which is one of the largest film and television archives in the world. Schools in the town include Berkhamsted School, a co-educational boarding independent school (founded in 1541 by John Incent, Dean of St Paul's Cathedral); Ashlyns School a state school, whose history began as the Foundling Hospital established in London by Thomas Coram in 1742; and Ashridge Executive Education, a business school offering degree level courses, which occupies the Grade I listed neo-Gothic Ashridge House.