Data used in visualizations is usually distributed in a standard format that can be shared. Even when the data is served from a database, the data is usually delivered in some standard format. Popular proprietary formats, such as Excel spreadsheets, are common, but most statistical data is stored or delivered in CSV, XML, or JSON formats.
CSV stands for comma-separated values. It's a very popular data format for public data. A CSV file is a text file that emulates a table. It usually contains one header row with the names of the columns, and one or more data rows containing value fields. Rows are separated by line breaks, and the comma-separated fields in each row form columns. It maps perfectly to an HTML table. This is a simple CSV file containing the population and land area of seven continents (Data/sample.csv):
continent,population,areakm2 "North America",579024000,24490000 "Asia",4436224000,43820000 "Europe",738849000,10180000 "Africa",1216130000,30370000 "South...