Software firms come in different shapes in sizes. For proof, just look at IBD’s software sector, which houses a whopping 10 subgroups. As of Thursday’s close, five of the groups ranked within the top 20% percentile of 197 groups ranked by IBD based on six-month price performance. (See table today on B13.) Big Data firms are housed in IBD’s Computer Software-Database group. The term has become increasingly common in technology talk.