High Quality Content by WIKIPEDIA articles! Presto is the layout engine for later versions of the Opera web browser (developed by Opera Software). After several public betas and technical previews, it was released on January 28, 2003 in Opera 7 for Windows, and as of Opera 11 it is still in use. Presto is dynamic: the page or parts of it can be re-rendered in response to DOM and script events. Presto is available only as a part of Opera browser or related products; the source or binary (DLL) forms of the engine are not publicly available. Subsequent releases have seen a number of bugs fixed and optimisations to improve the speed of the ECMAScript (JavaScript) engine.