Electric field lines are a graphical representation used to visualize and understand the electric field around a charged object or system of charges. They provide a visual depiction of the direction and strength of the electric field at different points in space.

Lines of Equal Electric Field:
One of the characteristics of electric field lines is that they are lines of equal electric field. This means that at any point along a given electric field line, the electric field strength (magnitude and direction) is the same. So, option 'A' is correct.

Drawing Lines of Electric Field:
Electric field lines are not drawn by hand or by any physical means. They are a conceptual tool used to illustrate the electric field. Therefore, option 'B' is incorrect.

Lines of Equal Electric Voltage:
Electric field lines are not lines of equal electric voltage. Electric field lines represent the electric field, which is a vector quantity with both magnitude and direction. Electric potential or voltage, on the other hand, is a scalar quantity that represents the amount of electric potential energy per unit charge at a particular point. So, option 'C' is incorrect.

Graphical Representation of Electric Fields:
Electric field lines are indeed a graphical representation of electric fields. They are drawn as lines that start from positive charges and end at negative charges, or extend to infinity in the case of isolated charges. The density of the lines indicates the strength of the electric field, with closer lines representing a stronger field. The direction of the lines indicates the direction of the electric field vector at each point. So, option 'D' is correct.

In conclusion, electric field lines represent a graphical representation of electric fields, and they are lines of equal electric field. They are not lines of equal electric voltage, and they are not physically drawn but rather used as a conceptual tool to understand the electric field.