A time-series is a collection of observations or measurements taken over a period of time, generally in equal intervals. Time-series only contain numeric data types and are indexed by one date field. In other words, time-series data are always sortable by date. Through our API calls, users can retrieve the entire time-series or any slice of it.
Many of Quandl’s databases are stored as time-series because financial data generally consists of two types: dates and observations, which perfectly fit the time-series format.
The time-series API gives you a choice of three formats (JSON/XML/CSV) and libraries for multiple tools.
You do not need any special software to use the Quandl API. All calls are made directly in your browser's address bar. You can also make API calls from your computer's command line (console/terminal), using curl, wget or similar utilities.