Electric current is the flow of charges. The electrons flow from higher density area of electrons to lowers density area of electrons. The terminal of battery which we called positive terminal of battery is the area of electrons with lower density of electrons and the negative terminal of battery is the area of electrons with higher density of electrons.
Current is denoted by "I" which is for current intensity. The symbol "I" is used by Andre-Marie Ampere. The conventional current flow from positive terminal of battery to negative terminal of battery, this concept was given by Benjamin Franklin. But today we know the electrons actually flow from negative terminal of battery to positive terminal of battery. But still we use conventional current direction for calculations.
Current is equal to flow of charges. Current (I) is equal to Charge (Q) in Coulomb / time (t) in seconds.
The rate of flow of charge in an electric circuit is called electric current. The unit of electric current is Coulomb per Second or Ampere.