E-learning cannot replace the face-to-face interaction that goes on in a classroom, but it can allow the enterprise a creative way to present information and offer learning at the moment it is needed, providing just-in-time learning to a mobile workforce. E-learning has usually employed a pull model, whereby employees must go to the information. However, new techniques are allowing more of a push model where workers can go to a site and set up a profile indicating the types of topics they want to learn about. When the information is available, the system pushes it to the user. E-learning message boards can also be employed that allow experts to answer user questions. Again, a push model is used and the person who asked the question receives a message indicating that the question has been answered. This saves time for users who do not have to constantly keep checking back to see if their question has a reply. Training modules are also being offered as podcasts, and training simulations are utilizing high quality graphics like those found in video games. Experts contend that the best approach to e-learning is one that also uses training with instructors. For example, IBM Learning Solutions has replaced its two weeks of instructor-led management training with an 18-month continuum, which uses a week of classroom learning followed by a week of collaborative e-learning and emphasizes the incorporation of experience gained in the field.