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Digital Signal Processing

Digital music, digital photos, digital videos: It's easy to forget that we live in a fundamentally analog world. Computers can cope with all that we see and hear only through the application of highly complex mathematics, a field known as digital signal processing (DSP).

Wherever you find digital media, DSP is at work, facilitated by a whole subcategory of specialized chips and circuits. DSP algorithms correct for errors while your optical drive reads the music off a CD. They're at work again as you compress the audio into an MP3 file, and again when you play it back through your surround-sound speakers.

DSP is to digital media as gears and springs are to a pocket watch. It works its magic below the surface: invisible, yet totally essential. It's safe to say that without it, virtually none of the digital technologies that we take for granted today--from DVDs to mobile phones, ink jet printers to DSL broadband--would be possible.

Managed Code

Programming is a lot more complicated than it used to be. Modern operating systems are like onions, with layers upon layers of subsystems to interconnect and manage. Worse, bugs and unnoticed security flaws, even ones that may have once seemed trivial, can be serious threats in the Net-connected era.

For a growing number of developers, the solution is to use platforms designed to relieve some of the burden. Programs written for such managed-code environments as Java and Microsoft's .NET don't run on the bare hardware the way traditional programs do. Instead, a virtual machine acts as an intermediary between the software and the system. It's like a robot nanny for computer programs, silently taking care of memory management and other housekeeping drudgery while keeping an eye out for potential security violations before they happen.

To an end user, a managed-code program may seem no different than a traditional one, but software that runs in a virtual machine makes for a more reliable, stable, and secure computing experience. And with .NET rapidly becoming the preferred platform for Windows development, managed code may soon be the norm, rather than the exception.