# series An array of series. Basic series information is stored in the main `squirrel.json` file. Extended information including series parameters such as DICOM tags are stored in a `params.json` file in the series directory.

### JSON variables :blue\_circle: Primary key\ :red\_circle: Required\ :yellow\_circle: Computed (squirrel writer/reader should handle these variables)

Variable	Type	Default	Description
`BidsEntity`	string		BIDS entity (anat, fmri, dwi, etc)
`BidsSuffix`	string		BIDS suffix
`BIDSTask`	string		BIDS Task name
`BIDSRun`	number		BIDS run number
`BIDSPhaseEncodingDirection`	string		BIDS PE direction
`Description`	string		Description of the series
`ExperimentName`	string		Experiment name associated with this series. Experiments link to the experiments section of the squirrel package
`Protocol`	string	🔴	Protocol name
`Run`	number		The run identifies order of acquisition in cases of multiple identical series.
`SeriesDatetime`	date	🔴	Date of the series, usually taken from the DICOM header
`SeriesNumber`	number	🔴 🔵	Series number. May be sequential, correspond to NiDB assigned series number, or taken from DICOM header
`SeriesUID`	string		From the SeriesUID DICOM tag
`BehavioralFileCount`	number	🟡	Total number of beh files (including files in subdirs)
`BehavioralSize`	number	🟡	Size of beh data, in bytes
`FileCount`	number	🟡	Total number of files (including files in subdirs)
`Size`	number	🟡	Size of the data, in bytes
params	JSON file		`data/subjectID/studyNum/seriesNum/params.json`
analysis	JSON object

### Directory structure Files associated with this section are stored in the following directory. `subjectID`, `studyNum`, `seriesNum` are the actual subject ID, study number, and series number. For example `/data/S1234ABC/1/1`. > `/data///` Behavioral data is stored in > `/data////beh`