In physical terms, the concept of electric field it is a little complex, but in order to understand it more easily we can say that it is analogous to the concept of a gravitational field. Although we cannot see it or touch it, we can verify its existence using a body of evidence.

To determine the existence of an electric field, we must place an electrified test charge in the region of the space in which there is an electric field, so we will verify that such a charge is subject to an electric force (), as shown in the figure above. Therefore, the sources of electric field are electrified bodies, which we call source loads (Q).
When moving an electrical test charge in an electrical field, it will be subjected to different strengths of electrical force. At each point of the electric field we define a electric field vectorO (). The intensity of this electric field is given by the following expression:

In the expression above, is the electric field vector and
is the electrical force vector on the test charge (
=what.
the vectors and
have the following characteristics:
- in module, F=|q|. AND
- same direction
- if the electric charge is positive (q > 0), and
have the same meaning
- if the electric charge is negative (q < 0), and
have opposite senses

By Domitiano Marques
Graduated in Physics
Source: Brazil School - https://brasilescola.uol.com.br/fisica/definicao-vetor-campo-eletrico.htm