Combat styles are coming with its upcoming content update, Legacy of the Sith, bringing a new way for Star Wars The Old Republic players to further customize and role-play their characters in the BioWare MMORPG.
Combat styles are a way to add more personality to your character. They aren't simply relegated to Jedi and Sith players, but every class will be able to change it up a bit and adopt a combat style that fits their personality. BioWare states that the idea here is to create the fully custom character they had envisioned with the launch of their MMORPG.
"When we first developed SWTOR, one of our goals was to enable players to create custom characters that reflected the ones you knew and loved from the Star Wars galaxy. So, when we designed our eight player classes, we tied each of them to the styles of combat we felt matched them best: For example, Bounty Hunters can fight with two blaster pistols like Jango Fett, Troopers use blaster rifles like Clone Troopers, and so on. In gameplay terms, these options are your character’s Class and Advanced Class, with each Class having access to only two Advanced Classes."
To that end, each class (and advanced class for that matter) will be seeing the ability to choose combat styles that suit your character's voice and personality. The team is doing that by separating your combat gameplay choice, i.e. Advanced Class, from your storyline choice, or regular class, as BioWare puts it. As such the team at BioWare are updating the names of each to make it a bit more clear in Legacy of the Sith, with Classes becoming Origin Stories and Advanced Classes becoming, well, Combat Styles.
There are still some limitations on which combat style is available for which Origin Story, such as Force-based classes having access only to Force-based combat styles initially. You can read more about combat styles on the SWTOR blog itself, and if you're interested in checking them out the team at BioWare is starting to make them available on the PTS, with the most recent being the Jedi Sentinel style.