lunes, 28 de mayo de 2012

Ten Usability Heuristics


Ten Usability Heuristics

by Jakob Nielsen    

These are ten general principles for user interface design. They are called "heuristics" because they are more in the nature of rules of thumb than specific usability guidelines.
Visibility of system status
The system should always keep users informed about what is going on, through appropriate feedback within reasonable time.
Match between system and the real world
The system should speak the users' language, with words, phrases and concepts familiar to the user, rather than system-oriented terms. Follow real-world conventions, making information appear in a natural and logical order.
User control and freedom
Users often choose system functions by mistake and will need a clearly marked "emergency exit" to leave the unwanted state without having to go through an extended dialogue. Support undo and redo.
Consistency and standards
Users should not have to wonder whether different words, situations, or actions mean the same thing. Follow platform conventions.
Error prevention
Even better than good error messages is a careful design which prevents a problem from occurring in the first place. Either eliminate error-prone conditions or check for them and present users with a confirmation option before they commit to the action.
Recognition rather than recall
Minimize the user's memory load by making objects, actions, and options visible. The user should not have to remember information from one part of the dialogue to another. Instructions for use of the system should be visible or easily retrievable whenever appropriate.
Flexibility and efficiency of use
Accelerators -- unseen by the novice user -- may often speed up the interaction for the expert user such that the system can cater to both inexperienced and experienced users. Allow users to tailor frequent actions.
Aesthetic and minimalist design
Dialogues should not contain information which is irrelevant or rarely needed. Every extra unit of information in a dialogue competes with the relevant units of information and diminishes their relative visibility.
Help users recognize, diagnose, and recover from errors
Error messages should be expressed in plain language (no codes), precisely indicate the problem, and constructively suggest a solution.
Help and documentation
Even though it is better if the system can be used without documentation, it may be necessary to provide help and documentation. Any such information should be easy to search, focused on the user's task, list concrete steps to be carried out, and not be too large.
I originally developed the heuristics for heuristic evaluation in collaboration with Rolf Molich in 1990 [Molich and Nielsen 1990; Nielsen and Molich 1990]. I since refined the heuristics based on a factor analysis of 249 usability problems [Nielsen 1994a] to derive a set of heuristics with maximum explanatory power, resulting in this revised set of heuristics [Nielsen 1994b].

lunes, 21 de mayo de 2012

wireframes

Wireframe



 Un wireframe es un bosquejo de la ubicación de elementos en una pantalla. Dependiendo de la etapa de desarrollo del proyecto, generamos el wireframe básico, que expresa los elementos de una pantalla genérica, aplicable a todo un sistema; wireframe tipo, que expresa la estructura de pantallas de una misma categoría, como canales o páginas terminales; y wireframe detallado, que especifica la composición de páginas específicas (se aplica especialmente a pantallas que implican la realización de acciones). A ellos debe sumarse, para ciertos proyectos en que tan relevante como ubicar los elementos en pantalla es simular el funcionamiento, los wireframes funcionales, que no se limitan a una estructura estática, sino que también permiten la navegación. Un wireframe grafica básicamente: Elementos de navegación: menús, accesos directos e hipervínculos. Elementos de información: contenidos de texto e imágenes. Elementos de interacción: herramientas o funcionalidades que el usuario puede realizar. Elementos de apoyo: ítems de ayuda y orientación, como mapas de navegación o faqs. Elementos promocionales: espacio dedicado a banners publicitarios o a destacados internos del propio producto.


10 herramientas para crear un wireframe

1. Mockingbird


Mockingbird is a web-based beta software based on the Cappuccino framework to create, link together, preview and share wireframes of your website or application.
It’s a clean and user-friendly interface, with drag and drop UI, interactive page linking, smart text resizing and the ability to easily share mockups with clients or colleagues with a direct link, make Mockingbird one of the best wireframe tools available.
As it’s web-based, it means you can create and share mockups from anywhere. It will be interesting to see just how good Mockingbird is when it comes out of beta and the full version is released.

2. Lovely Charts


Lovely Charts is an online diagramming application, that allows you to create flowcharts, sitemaps, organization charts and wireframes.
One of the key features is the application’s ability to make assumptions based on the type of diagram you’re drawing, and thus streamline the drawing process. The History management feature is extremely useful, keeping 20 states of your diagram in memory should you wish to go back to an earlier version or undo any changes.
There is a powerful yet simple tool set provided, with an extensive library of crafted symbols to suit most requirements.

3. Cacoo


Cacoo is a user-friendly online drawing tool that allows you to create a variety of diagrams, such as sitemaps, wireframes and network charts.
The drag and drop UI means creating diagrams is relatively simple; there are also a number of stencils to utilize which could make the process even more efficient. Unlimited Undo is a neat feature with the history of all modifications saved, meaning you can undo right back to the start.
Numerous users can also work on and complete the same diagram simultaneously with the application supporting real-time collaboration.

4. Gliffy


Gliffy is a web-based application which allows you to create process flow diagrams, org charts, floor plans, business processes, network diagrams, technical drawings, website wireframes, and more. It uses a drag and drop UI with the ability to add boxes, buttons, and lines from the tool shape library to anywhere on the page. Then you can easily add text to create a clear, concise mockup.
You have access to a complete library of shapes and can even import your own images, like logos and backgrounds, to complement your diagrams. You can share and collaborate with anyone, on any platform, in any location, while having the ability to protect and track changes.
The Gliffy API (beta) also makes it possible for developers to add Gliffy diagramming features to their existing web-based applications based on a simple to use framework.

5. Lumzy


Lumzy is a mockup and prototype creation tool for websites and applications. You can add events to controls, place controls inside other containers and emulate your project with easy page navigation triggered by user actions.
Real-time collaboration is one of the key features, with tools for team editing, a chat engine for deliberating over designs and file versioning. Lumzy is also the only mockup tool with a real image editor built-in — simply grab any picture from your drive and edit it, apply hue, saturation, adjust contrast, and so on, and then add it to your project.
The Pro version is white label and can be integrated into an existing platform or hosted on your own server which may be of interest to companies working with confidential information.

6. Mockflow


Mockflow is a web app based on the Adobe Flash Platform. It has a clean, minimalistic, organized interface and the editing feature-set set is extensive.
You drag and drop components into a mockup to create the wireframe with the ability to add pages and map out an entire site and it’s structure. The built-in components are extensive, from charts and ads to menus and dropdowns. The ability to upload your own images to use, as well as the option to choose from a set of stickers of common site elements, such as social networking and e-commerce images, make the process of ‘building’ the mockup pretty efficient.
You can talk over the real-time chat and invite others as editors or viewers, depending on the level of editorial power you’d like each member to have. Editors have the ability to make changes to the wireframes, while viewers are limited to reviewing and commenting.
The MockStore is a wonderful add-on service that provides third party components and templates shared by the user community.

7. Pencil Project


The Pencil Project is an open source tool for making diagrams and GUI prototyping that everyone can use. It’s available as a Firefox add-on or as a standalone application (Linux and Windows only). Pencil essentially installs an entire drawing application into your Firefox browser and gives you the ability to display, save, and load an external canvas, together with a palette of shapes.
Of interest is the Stencil Generator which allows you to create your own collection of stencil shapes by pointing the generator to a folder of image files. The Clipart tool lets you search through the library at openclipart.org and directly drop the images right into your Pencil document. Pencil also supports the use of external objects; both raster and vector images can be imported using copy-paste or drag and drop.
The final prototype can be exported as a PNG image, web page, OpenOffice file, PDF or DOC file. If you’re a dedicated Firefox user, then Pencil could be an essential tool for visually expressing conceptual ideas on the fly. It even won the Mozilla award for ‘Best New Add-On’ in 2008.

8. SimpleDiagrams


SimpleDiagrams is a small desktop application that helps you express your ideas quickly and simply with just enough functionality to describe a thought or capture a process. It’s built on the Adobe AIR platform, so will run smoothly on Mac, Windows and Linux.
You can drag, drop and size symbols from libraries, add photos and post-notes and export your diagram to PNG.
It may not be a fully-fledged diagramming tool, but because SimpleDiagrams is so basic, you will be creating wireframes or diagrams within minutes.

9. Denim


Denim is a free multi-platform desktop app that supports sketching and allows design at various refinement levels. It’s an efficient tool for early stage brainstorming and wireframing.
Two main features within Denim are Components, which enable you to create widgets that can be reused and Conditionals, which allow you to create transitions between pages depending on the end-users’ actions, resulting in a more interactive experience.
It’s a simple yet effective tool and allows for easy annotation using editing gestures.

10. Website Wireframe


Website Wireframe is a very simple web-based tool for building wireframes in a matter of minutes. A link to view the wireframe can be sent through email, instant message, or mobile phone, and then the wireframe can be easily updated based on feedback, discussion, ideas and suggestions.
The key to this tool is the simplicity of usage, lending itself to speed, both in wireframe creation and sharing. It is free to register and use and works in most modern web browsers.
It may not be particularly sophisticated, however it’s simplicity and efficiency is perfect for those who want an alternative to tools with a higher learning curve.

lunes, 14 de mayo de 2012

Interfaz de usavi

Usabilidad


Atributos de Usabilidad
La usabilidad es una cualidad demasiado abstracta como para ser medida directamente. Para poder estudiarla se descompone habitualmente en los siguientes cinco atributos básicos [Nielsen93]:

· Facilidad de aprendizaje: Cuán fácil es aprender la funcionalidad básica del sistema, como para ser capaz 
de realizar correctamente la tarea que desea realizar el usuario. Se mide normalmente por el tiempo empleado con el sistema hasta ser capaz de realizar ciertas tareas en menos de un tiempo dado (el tiempo 
empleado habitualmente por los usuarios expertos). Este atributo es muy importante para usuarios noveles.

· Eficiencia: El número de transacciones por unidad de tiempo que el usuario puede realizar usando el
sistema. Lo que se busca es la máxima velocidad de realización de tareas del usuario. Cuanto mayor es la 
usabilidad de un sistema, más rápido es el usuario al utilizarlo, y el trabajo se realiza con mayor rapidez. 
Nótese que eficiencia del software en cuanto su velocidad de proceso no implica necesariamente eficiencia 
del usuario en el sentido en el que aquí se ha descrito.

· Recuerdo en el tiempo: Para usuarios intermitentes (que no utilizan el sistema regularmente) es vital ser 
capaces de usar el sistema sin tener que aprender cómo funciona partiendo de cero cada vez. Este atributo 
refleja el recuerdo acerca de cómo funciona el sistema que mantiene el usuario, cuando vuelve a utilizarlo 
tras un periodo de no utilización.

· Tasa de errores: Este atributo contribuye de forma negativa a la usabilidad de un sistema. Se refiere al 
número de errores cometidos por el usuario mientras realiza una determinada tarea. Un buen nivel de
usabilidad implica una tasa de errores baja. Los errores reducen la eficiencia y satisfacción del usuario, y 
pueden verse como un fracaso en la transmisión al usuario del modo de hacer las cosas con el sistema.
· Satisfacción: Éste es el atributo más subjetivo. Muestra la impresión subjetiva que el usuario obtiene del 
sistema. Algunos de estos atributos no contribuyen a la usabilidad del sistema en la misma dirección, pudiendo ocurrir  que el aumento de uno de ellos tenga como efecto la disminución de otro. Por ejemplo, esto puede ocurrir con la facilidad de aprendizaje y la eficiencia. Es preciso realizar el diseño del sistema cuidadosamente si se desea tanto una alta facilidad de aprendizaje como una alta eficiencia; siendo el uso de aceleradores (combinaciones de teclas que ejecutan operaciones de uso habitual) la solución más común para conjugar ambos atributos de usabilidad.

La usabilidad del sistema no es una simple adición del valor de estos atributos, sino que se define para cada 
sistema como un nivel a alcanzar para algunos de ellos. Estos cinco atributos pueden descomponerse a su vez para conseguir una mayor precisión en los aspectos de usabilidad en los que se quiere poner mayor énfasis.

lunes, 7 de mayo de 2012

Validar paginas web


Tener un código fuente válido es un aspecto del diseño web que muchos diseñadores pasan por alto. Tener un código bien hecho es importante para que la página se vea bien en todos los navegadores, cargue más rápido y el acceso de los robots de los buscadores sea mejor.
Tampoco creo que sea necesario ser un fanático de los códigos perfectos, pero si es conveniente ver cuántos errores tiene tu web y reparar los que creamos necesarios. Algunas herramientas para ello:
  • Site Report Card: Además de comprobar posibles errores del código fuente de tu página, revisaenlaces rotosmetatagspalabras clave, popularidad del sitio, etc.
  • W3C validación: este es el servicio de validación del W3C, que son los que se encargan de crear los estándares de la Web, por lo que hay que tenerlo muy en cuenta a la hora de validar el código de una web.
  • Feed Validator: como no también hay validadores de feeds. Este es muy sencillo, le indicas la dirección de tu feed y te informa de su estado.