Prior to editing the video, the footage must first be logged. Interviews are transcribed word-for-word and b-roll is described (providing information on type of shot, location and other brief descriptions. Logging is usually a post-production activity, but sometimes the logging can begin during the production stage. Scripts for news packages and documentaries can't be completed without first logging the footage.

As a record of what was shot, logging helps speed up the process of looking for the most usable footage without always going back to the original media. It also records whether the footage is good or bad, or if there was an issue with the audio. The start of the footage (b-roll shot or interview SOT) is always matched with its timecode.
Think of timecode as a numerical address for each frame of video, which is read by hours, minutes, seconds and frames. Reporters in the field can observe the timecode being generated by the camera to make rough notes about where a SOT begins and include that information in their rough scripts. Further, if the reporter is not present during the editing process, the script with timecodes will make locating the footage easier.

Editing Workflow
Edit Terms
Adobe Premiere Guide
Fast Package Editing Instructions
Video Compression Formats