What's Basal and Bolus?

In short: Insulin!

Bolus is your fast-acting insulin. So what you injected for your meals or correction, for example.
Basal is your other type of insulin. Your slow-acting insulin, a.k.a. long-lasting, a.k.a. baseline, a.k.a. basal insulin.

In pump therapy only fast-acting insulin is used and is delivered as a bolus at mealtimes or corrections, or pumped in small quantities throughout the day and night, as programmed in the pump. In this case, the basal is often referred to as the basal rate.