Burlesque is an eclectic and broad genre of live performance. While it is hard to define; audiences can expect a mix of vintage glamour and modern tongue in cheek, adult humour. In modern times, Burlesque usually includes elements of striptease but also uses elements of dance, mime, acting, spoken word and even circus arts.
Although the 'art of tease' is much a part of Burlesque, Burlesque and striptease are not the same thing. The intention of striptease is to titillate or arouse where as 'Burlesque' usually aims to amuse, surprise and make people laugh. Burlesque was originally used to describe performances in the Victorian era that were a caricature or a parody. The word "burlesque" comes from the Italian word "burlesco" which comes from the Italian word "burla" which means a "joke" or "mockery". Thus although most Burlesque dancers are women, Burlesque crowds tend to be comprised primarily of women and mixed couples.
These days Burlesque also implies a performance has a vintage or retrospective quality, although this is not strictly be the case. Many Burlesque acts are a tribute to vintage glamour and celebrate the female form in its curvy glory. Often these very vintage inspired acts are more on the serious side. For these reasons 'Burlesque' often conjures the image of a vintage portrayal of striptease. Many consider this to be a more classic and sophisticated way to enjoy adult themed entertainment.
As you can see there is not a simple answer to the question 'What is Burlesque?'. As a performance genre it constantly breaks the rules, including its own and can encompass anything from; bawdy humour; satirical social comment; classic vintage glamour; or sensual striptease.