• The letters C/B/A+ refer to the first three divisions of swimming and give swimmers a way to measure their progress. C is the beginning, B are faster times and A are the fastest times. These divisions give swimmers incentive to shoot for the next division's standard.
• Here are the 8 and Under Standards, and here are the standards for older swimmers.
• Time standards change by age and are different for boys and girls. When looking at the Time Standards, be sure to look at Short Course Yards (SCY) or Long Course Meters (LCM), as the times for the same event will be different.
• After your first meet, you can see what division your swimmer's time falls into. Each group of swimmers in a given event are ranked according to their time and awards are given by division. Therefore, a new swimmer in the C division will be ranked against other swimmers with times in the C division. In the same event, there could be swimmers with B times, and they're ranked against each other.
• You may also hear "JO times" and "Far Western times" which refer to qualifying times for the Age Group Championships (previously called the Junior Olympics) and the Far Western Championships. These are faster than A times.

The Pacific Swimming site has more information about Time Standards.