Previous : 348 Thousand
Forecast : 345 Thousand

Definition :

A measure of the number of people filing first-time claims for state unemployment insurance. Issued by the Labor Department on a weekly basis; on Thursday at 8:30 a.m. Eastern time, the data is for the week ended the previous Saturday.

Why is it useful?

Occasionally moves market, timely. Considered a good gauge of the condition of the labor market and good indicator to the tone of the employment report.
The series are volatile and subject to revisions. The four-week average is used to gauge the underlying trend in claims.
The effect of the rising number is negative for both the dollar and the indices.