> Dynamic languages are languages that don’t necessarily need variables to be declared before they are used. Not exactly true. You do need to declare variables

> Dynamic languages are languages that don’t necessarily need variables to be declared before they are used. Not exactly true. You do need to declare variables in some dynamic languages (var in JavaScript, for example), but you don't need to declare their type. Anyhow, the whole question is a little irrelevant. The language you pick for your startup is among the factors least important to its success. Just pick a reasonable language that you are productive with, that has library support for the stuff you need, and that works well on the operating systems you care about, and that will be fine.