1 converts written data into sound waves. 2  converts the sound waves from a voice into a digital signal. 3  converts letters from the keyboard into digital format. 4  converts digital sound waves into analog sound waves.
Travel agencies make their money in a variety of ways. The products agents sell have built-in fees that result in a profit for the agency. The amount of the fees and the ways in which they are earned and distributed differ by the type of product sold and the suppliers who provide that product to the agency.
READ MORE: Travel agents still play vital role for business travelers. It's not all good news, at least job-wise. According to the Bureau of Labor Statistics, there were 64,680 full-time travel agents in 2012. A decade before, there were 95,360. Revenues, however, have gone up. Travel agencies generated $17.5 billion in revenue in 2011, up from $9.4 billion in 2002, according to the Census Bureau.