plpgsql string concatanation

Is it posible to do string concatanation in plpgsql?

Somthing like:

sec := ''some string here'' . NEW.id;

Is there a way to do this? I need te value of that new string for things that
come after, and couldn't find much in the PL documentation.

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Martín Marqués        | select 'mmarques' || '@' || 'unl.edu.ar'
Centro de Telematica  |  DBA, Programador, Administrador
             Universidad Nacional
                  del Litoral
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