Knockout vs pug (Jade)

Knockout uses HTML5 data attributes to bind HTML elements to data objects in javascript. This allows more work to be done by the framework rather than requiring you to specify where data should be bound in the javascript. The data binding is very intuitive as the bindings are done within the HTML itself in the location it should be bound.

Has a low entry barrier and an easy learning curve. It's especially easy to learn for beginners.

Bindings in Knockout can also be used to control the generated structure of the HTML. There are bindings provided to allow for iteration and conditionals. The structure of the html reflects the structure of the data so iterative elements are bound to arrays in the data model. Having the HTML structure maintained by bindings keeps the templating simple, easy to read, and maintain.

Knockout also allows for string based templating so you can use whatever templating library you prefer.

Supports a large number of browsers, including IE6.

The excellent tutorials with built-in exercises are a great learning experience, even for people without prior MVVM and data binding experience.

Models in Knockout can be watched to keep the page data up to date by using observable objects. The observables notify Knockout when data is changed and automatically updates the page when this happens. By having Knockout maintain this relation, it keeps the front end code cleaner and simpler, and by enforcing a consistent pattern with observables the methodology can be more robust.

One can do a lot of things and it keeps self references and other types of loops under control.

Knockout does one thing, and does it well. It doesn't try to take on more than one area. It does MVVM data binding and that is it.

Using components is a great way of breaking up large modules into simpler ones.

Jade supports mixins. These not only make your templating job easier but are also super-easy to read.

The logic in Jade is done with native JavaScript. This means there's less of a learning curve and it'll be easier to get other developers up to speed.

One of the distinguishing features of Jade is its clean syntax. Elements are created with CSS selector syntax which makes the template consistent with your style sheet and JavaScript element selector library.

With Jade you can quickly overview the hierarchy of a template.

Apart from their functionality all template engines need to be efficient in terms of the time they require to render a page. Jade beats most of its competitors in this area, it is highly optimized to deliver good performance on both the server and client ends.

By using the extends and block keywords, sublayouts can be made with intuitive syntax.

Filters make it easy to embed compiled languages such as coffeescript or markdown directly into the template. A filter will allow you to keep your inline code and content consistent with the rest of your codebase so you can continue using your prefered language with your outputted HTML.

Jade allows embedding regular JavaScript code directly within the template.

In addition to JavaScript, you can reuse Jade templates in Scala, PHP, Ruby, Python and Java.

There's an interactive documentation available here that allows you to play around with code examples and watch the results in real time.

Jade compiles to a JavaScript function that produces the ultimate output. This interim format makes it useful for embedding in conditions where you're trying to save space or decrease processing requirements.

Jade is awesome at templating structural markup, but that's not all Jade is awesome at. It also allows you to use markdown within your template itself which will render to a beautiful HTML page.