I5, or I 5 may be: · IBM AS/400 iSeries line of minicomputers · i5 an early 2000 girl group · Interstate 5 · Straight-5 or "inline-5" I 5 is a Swedish regimental designation (5th Infantry Regiment) that has been used by the following units: · Andra livgrenadjärregementet (1816–1927) · Jämtlands fältjägarregemente (1928–1974, 1990–) I5