LTV (Long Term Visa) vs STV (Short Term Visa)

Schengen visa shorthand. STV is the Type C visa: stays under 90 days in any 180-day period, issued under the common EU visa code. LTV is the Type D national visa: stays over 90 days (work, study, family), issued unilaterally by a single member state under its own immigration law rather than shared EU rules.