Prima Sans family (Bitstream library) contains 4 fonts.
Prima is a series of fonts designed at Bitstream by Jim Lyles (Sans and Serif) and Sue Zafarana (Sans Mono), released in 1998.
The fonts have been tuned to give exceptionally good quality at low screen resolutions. The fonts are therefore suitable for sustained use in browsers and other applications where users read for long periods from the screen. Of course, Prima looks great printed out too.