The article talks about how odds and odds ratios are used to measure the likelihood of an event happening, like getting a disease. Odds ratio compares the odds of an event between two groups, like people exposed to a risk factor and those who are not. This ratio is often used in case control research. When an event is rare, the odds ratio can be seen as a relative risk, which shows how much the risk of the disease increases in people with a certain condition. This helps us understand the impact of different factors on the likelihood of getting a disease.