There are basically four major components to solar electric systems; Solar Panels, Charge Controllers, Batteries and Inverters. All of these components are necessary to have a functioning Solar Electric (PV) system. 

           You start with the solar panel, this is the foundation of the system. This is what produces the energy or, "generates the electricity". They also charge your batteries if you have them in your system.  If you connect several solar panels together, you have created a solar array. The size of the solar array, and your location, determine the amount of electricity that will be produced. If you live in the southern part of the United States such as Florida, Southern California, or Texas, you will produce more than if you live in the northern areas, such as Washington State, Michigan or Maryland. In general, the farther south you live, the more electricity your system will produce. To find out how much power can be produced in your area, go here. 

           Charge controllers come in several different sizes and models. They all basically do the same thing. The charge controller prevents the solar panel or array from overcharging your battery. 

           Batteries store the energy that your solar panels produce during the day. Generally, the battery provides the power to the loads in the system. The power provided by the solar panel or array, is not compatible with the appliance and electronic loads that are in a house or system. Solar panels produce DC power, and household electrical systems are based on AC. Batteries store the charge produced during the day, and then provide your power needs at night.

           The fourth component in the system is the Inverter. The inverter takes the DC energy stored in your batteries and converts it into  AC power for use in your home. Inverters, like charge controllers, come in several different sizes and models. Inverters are  rated by wattage and the quality of their output. There are small inverters that can plug into your car 12 volt outlet and power small devices, or you could have a 4000 to 11,000 watt inverter system that powers your home.

          All of these components can be put together in many different ways. Other items such as wire, circuit breakers, and mounting systems for the solar panels are also needed for a complete system. 

Remote systems are used in areas where there is no utility power lines or other sources of power. These systems are often used for cabins or other remote buildings, where the costs of bringing in power lines are prohibitive. These systems generally consist of:

An array of Solar Panels, a Charge Controller, Batteries, and an Inverter for AC Loads. If you intend to run your building on DC power, you can eliminate the inverter.

Obviously one of  the advantages to this system is not having to relay on the local utility company for your power. Also in the long run you will save money over having to run power lines in to your area.
The disadvantage being a high initial cost for installing the system, and the time involved in analyzing your power requirements in order to install the system that will meet your needs. However, over a period of time the system will pay for itself in savings.

This is a system in which you have:

A Solar Array, an Inverter, and you are connected to the local "Grid", or utility.

This system takes the power generated by the Soar Panels, uses an inverter to change the DC into AC, and feeds it into the local utility grid. If your system is large enough to produce more power than you use, your power meter will even spin backwards, essentially "selling" power back to the utility. Because there are no batteries in this system, it has a much lower cost per watt produced. However, if the utility system fails, your system will shut down also.

This system works like the battery/surge protectors that are made for home PC's. This system consists of:

A Battery Charger, Batteries, and an Inverter to convert the DC from the batteries to AC for your household system. 

This system takes the power from your utility and charges the batteries, holding them fully charged, waiting for a power failure on the utility "grid". When this happens, the batteries are switched in line automatically and start providing your power. This works well for area's that see many outages for short periods of time. The drawback being, that the amount of time you can continue to run, is dependent upon the amount of battery storage you have.

This system is essentially the same as the Grid Tied system mentioned above. It utilizes:

A Solar Array, an Inverter, and also a battery storage system.

With this system, the batteries are charged by the Solar Array. When the utility grid fails, the batteries are switched inline automatically, powering your household systems. The advantage to this system is that you have both, a battery backup, and the ability to run your power meter backwards, "selling" your excess power back to the utility when the batteries are fully charged.
The disadvantage to this system is that it is the highest cost per watt of any of the systems, and will take longer to recover the expense of putting in the system.