TAL is an HTML templating mechanism designed to provide enough power to create any possible HTML output from a template yet at the same time maintain the distinction between presentation logic and program logic.
TAL's syntax tries to be as HTMLish as possible, this is to help graphic designers, who can't be bothered, and really shouldn't be bothered, to learn a new syntax, and the most common design tools, which work best with tags and attributes.
A TAL template is an object (represented internally as a function and externally as a text file or a string) which, given an environment mapping names to values and a generator which is able to locate included templates, produces some text.