Different materials have different electrial properties. Metals are good conductors and electric charge can move easily over metal surfaces and through metal wires. Glass and air and plastic are good insulators and electric charge does not move through them easily.
When certain materials rub against each other, that friction work can produce a separation of charges. When animal hair is rubbed against a rubber balloon, electons are moved from the hair (which becomes positively charged) onto the balloon (which becomes negatively charged). This separation of charge contains potential (stored up) energy that often causes it to stick to other materials.
The energy stored in a charged object can be used to separate charges in a neutral object by a process called induction. If a negatively-charged object is brought near a neutral object, the charges in the neutral object shift apart so that the negative charges are pushed away and the positive charges are drawn towards the negatively charged object. A positive charge will shift the other way, but in both cases the opposite charges are attracted closer to each other and become the stronger force. This is how static electricity causes objects to stick together.
The energy stored in a charged object can also flow to another new object by conduction. If an object is negative (more electrons than protons), the extra electrons will spread away onto the new object. If an object is positive (less electrons than protons), it will draw electrons away from the new object. How fast this happens depends on how well the materials conduct. When the charge energy in a cloud is enough to conduct through the air, we see lightning.

When charge flows, we measure how fast it moves with current. If 1 Coulomb of charge moves by every second, that is 1 Ampere of current. Current is "driven" by voltage. Voltage measures the average energy per charge. If 1 Joule of energy is stored in each Coulomb of charge, then a voltage of 1 Volt is established.
Conductors have different abilities to move charge. If 3 Volts is applied across different materials or different lengths or different thicknesses of the same material, then different amounts of current can result. If the voltage goes up, the current goes up, too, but the ratio between the voltage and current generally stays the same. We call this ratio a measurement of the resistance of the object. So, the current that would flow through a material can be predicted by dividing the voltage by the object's resistance, and the voltage across a material is the current times the resistance. This is Ohm's Law.

When voltage is used to power devices, the path from one end of the voltage source (eg, battery) to the other is called a circuit. If the path is a sequence of devices (resistances) through which electricty has to travel in order, then this is called a series circuit. If the path branches so that electricity can travel through one device OR another to get to the other end, then this is a parallel circuit.
For a series circuit, the total or equivalent resistance on the battery is the sum of the resistances of everything in the series circuit. This means that adding a device, even if it has a very low resistance, will decrease the current. If a 20-Ohm and 40-Ohm resistors are connected to a 6-V source, then the current would be about (6V÷(20Ω+40Ω)) = 0.1 Amps (or 100 mA). Another feature of a series circuit is that when one device fails to conduct the electricity, the current throughout the circuit stops. This is why switches and fuses are connect in series (without a branch around them), so that they can stop the current.
For a parallel circuit, the total or equivalent resistance on the battery is the inverse of the sum of the inverses of each resistance in the parallel circuit. This means that adding a device, even if it has very high resistance, will increase the current. If a 20-Ohm and 40-Ohm resistors are connected to a 6-V source, then the current would be about (6V÷(1/(1/20Ω+1/40Ω))) = (6V÷(40/3Ω)) = 0.45 Amps (or 450 mA). This creates the danger of overloading, because if enough devices are added to a paralel circuit, the current may get very high. When high current passes through wire, it heats up (similar to in a toaster) and fuses or circuit breakers are often added (in series) to stop the current if it gets high enough to become a fire hazard. Another important feature of a parallel circuit, because each device is in a separate "branch", is that when one device fails to conduct, the current only stops through that device's branch; it continues to the other devices in the other branches.

All charges experience an electric force that draws together charges of opposite types and pushes apart charges of the same type. We call these two types "positive" and "negative". If the charges are farther apart, the force between them is less. Just like with gravity or sound loudness or light brightness, it obeys the inverse-square law, so if charges are twice as far away, the force between them is one fourth what it was.

Opposite charges are attracted and like charges are repelled. When charges have the ability to move because of these rules, they have a potential difference, similar to the difference in height that something has when it has the ability to fall to a lower gravitational potential energy. For electricity, this potential difference is measured by voltage and shows how much cause or reason there is for charges to flow as electric current. If voltage and current are high, then there is a high amount of power flowing.
Current is charge per time and Voltage is energy per charge. Multiplying them, the charge units cancel and we get energy per time which is power. The current or flow does not need to be high for us to get a lot of power if we're using high voltage. This is why power plants produce high voltage electricity; handling and transmitting high current is more difficult and less efficient.
A helpful analogy can be to think of people migrating (like for vacation or retirement or from civil war or natural disaster). The people represent energy that has a reason to "move", their vehicles represent charge which "carries" them, and the path they take is the circuit. The path, depending on "road" conditions, has resistance. The vehicles carry the people and can be packed with people or just have a driver. How "packed" the charges are with energy is voltage. How fast the cars move on the path is current, which is obviously affected by how much the people want to move and how easily the road lets them move. You can hopefully see that it takes cars that are both packed and moving fast to get the people to move fast. This is how both voltage and current are factors in electrical power.

When electric charges move, a spinning magnetic field ripples out of their sides. We can see this when a magnetic compass is brought near a wire carrying current. If a magnetic field moves, a spining electric field ripples out of its sides. When can see this by moving a magnet through a solenoid connected to a voltmeter.
This perpendicular interaction lets us move or create magnets with electricity, like in a speaker or electromagnet. We can also move or create electricity with magnets like in an electric motor or generator.