An audio commentary is an additional audio track, usually digital, consisting of a lecture or comments by one or more speakers, that plays in real time with a video. Commentaries can be serious or entertaining in nature, and can add information which otherwise would not be disclosed to audience members.[1]
In accounting terms, operating expenses, or OE, and cost of goods sold, or COGS, are both considered expense accounts. In short, they measure different ways in which resources are spent in the process of running a business.
Costs should be expensed when they are used up or have expired and when they have no future economic value which can be measured. For example, the August salaries of a company's marketing team should be charged to expense in August since the future economic value of their August salaries cannot be determined.