Vinyasa Flow is an intelligent way of sequencing postures towards a peak pose and/or theme utilizing breath-synchronized movement. This style allows for a lot of variety, but will almost certainly include Sun Salutations. Expect movement, not just stretching. Whether the class is fast or slow, includes chanting, or is very alignment-oriented will depend on the individual teacher. You may find this style of yoga more enjoyable if you have experienced some yoga "basic" classes.