How a miniature wargame is played depends entirely on the rules used.  In very general terms, most  rules are set up around moving and "firing" of model soldiers at each other.  Miniatures are moved up to a certain distance as prescribed by the rules.  Usually, a type of miniature (foot soldier or tank, for example) is given a "maximum move" in inches or centimeters it can traverse across the playing area; terrain features or obstacles such as hills, woods, barbed wire can reduce the permitted movement by varying amounts, depending on how difficult it would be to cross it.   To fire at enemy miniatures, the distance on the gaming table from the miniature to its target is measured to determine "range".  A chart is consulted which gives a value which must be thrown on a die or set of dice to determine if the "shot" actually hits the target.  Terrain features come into play again as a thick wood or a high hill between two miniatures blocks their "line of sight" or ability to actually "see" each other and fire.

Although it has been around for as long as there have been toy soldiers, the popularity of wargaming in miniature has grown much since the early ‘60s when the availability and quality of model soldiers, tanks, guns and other miniatures really began to take off with such companies like Airfix. 

With respect to fictional battles, there are large numbers of gamers who play fantasy or science fiction based wargames.  In fact, they vastly outnumber those of us who are strictly historical players! 

Wargames can be land battles using soldiers, tanks and guns or naval battles using model ships (and perhaps airplanes).  There are some miniature wargamers who game exclusively with model aircraft.  Of course, fantasy and science fiction games can be subdivided similarly into land, sea and air games, as well as space games with star ships and space station models slugging it out!
 
 

Setting Up a Gaming Area: "Museum Quality" Terrain is NOT a Necessity! As already mentioned, you can wargame on a table or, if your knees can handle it, on a basement or other floor or even outside in your back yard.  The area you'll need depends on the model scale and number of miniatures you're using as well as the period (Napoleonic battles, for example, are contrasted with modern engagements by the density of troops on the gaming area).  Scenery used is a personal choice.  By all means, a lot of effort can be put into making realistic scenery, but it is NOT necessary.  Throwing a blanket or towel over some books suffices for hills.  Chalked out rivers or wood lines will also serve the purpose, as do buildings made of Lego or paper.  Regardless of how "realistic" the scenery looks, you will find the battlefield takes on a life of its own as you play.  A hill becomes an objective for you to capture, to avoid being decimated by the enemy artillery emplaced there.  You become focused on the hill; later, you will remember more the pitched miniature battle fought rather than how "nice" the hill looked!

Legos are just fine! Click here to see a game using both Legos and paper houses played on a basement floor; river made of blue tissue paper! Click here to see an example of  outdoor gaming. Contrast the above with this picture (click here) The terrain didn't make a bit of  difference with regard to the enjoyment of any of these games!

In the naval department, 1/1200 and 1/2400 are very popular scales for ships from the Age of Steam and after.  1/600 is a frequently used scale for pre-20th century naval warfare and we are currently using this scale for US Civil War river and open sea engagements.
 

Rules - Buy Them or Write Them Yourself - & Game Scale There are a large number of rules available which you can purchase.  Many of the very popular sets have, at their heart, a sequence which takes place each turn.  For example, a turn could consist of 6 steps: 1) side A moves; 2) side B moves; 3) resolve direct fire; 4) resolve indirect artillery fire; 5) resolve close combat; and 6) check morale.  Recently, a number of rule sets have been published which do not follow this "traditional" game sequence and the demonstration game set up here today uses one of these rule sets, Crossfire.  Rules are geared toward a certain level of play and place emphasis on certain things.  Skirmish rules generally deal with individual soldiers and have enough detailed rules so that 10-20 troops and maybe a tank per person are the limit - these rules can often be very much like role-playing games.  Other rules may have lesser detail and be 1:1 - one figure represents one soldier or have a higher "miniature scale".  Higher miniature scale means the rules have a figure (or group of figures mounted on a stand) or vehicle represent a squad (or individual vehicle), platoon or company.  These rules with higher figure scale allow larger battles to be fought and tend to focus on the problems by higher level commanders as opposed to individual soldiers.  Of course, you can always write your own "home grown" rules.  These can be heavily researched and/or, based on your knowledge or readings (or just war movies ) of the period in which you are interested.  Often, people who buy published rules sets write their own "house rules" or even base their own home grown rules on one or more published sets.

Read the introduction to  Crossfire, here, for an insight as  to why we like these rules so  much! For an overview of various  historical rules, browse about that portion of  The Miniatures Page