The HP ProBook is a brand of affordable business notebooks made by HP Inc. The ProBook series are aimed at mainstream business users and are cheaper than the higher-end EliteBook series.
S-Series
In April 2009, HP introduced the ProBook s-series (standard/essential) notebooks, which consisted of the Intel powered 4410s, 4510s, and 4710s (14", 15.6", and 17.3" screens, respectively) and the AMD powered 4415s and 4515s (14" and 15.6" screens, respectively). This was followed by the introduction of the 13.3" ProBook 4310s in June of the same year. The s-series was updated in 2010 with Intel Core i3, i5, and i7 processors, a brushed aluminum case, chiclet keyboard, and multitouch ClickPad. Updates to the line in 2012 included a new exterior aluminum design.
B-Series
The ProBook B-series was announced on October 13, 2009, replacing the previous HP Compaq B-series. Two AMD powered models were announced—the 14" ProBook 6445b and the 15.6" Probook 6545b. Their Intel powered counterparts were announced three months later as the 14" ProBook 6440b and the 15.6" Probook 6540b. The B-series was updated in 2012 with the Intel-powered 6470b and 6570b, and the AMD-powered 6475b.
M-Series
HP launched the 5310m in September 2009. The 5310m was enclosed by an aluminum and magnesium case, weighed under four pounds, and was less than an inch thick. The M-series was updated in September 2010 with a 5320m, closely followed with the release of the 5330m in May 2011 which featured a dual-tone aluminum chassis and Beats Audio.
