Endgames are typically classified according to which pieces (material) remain on the board. Keep in mind that material advantages in endgames are usually decisive, though with precise play it’s still possible for the disadvantaged player to eke out a draw or even a win, depending on the character of the endgame.
1. Pawnless Endgames are also called basic or fundamental endgames. These tend to feature one or two pieces against an enemy king. (For example, a king and a queen against a king, a king and two bishops against a king, etc.)
2. Rook Endgames (also called rook-and-pawn endgames) can be highly choreographed affairs, often requiring dozens of moves before checkmate can be achieved. To get a handle on these endgames, study the Philidor and Lucena Positions.
3. Endgames featuring two minor pieces against a rook depend heavily on initiative. In these situations the exact number of pawns and the pawn structure are extremely important.
4. Bishop-and-pawn endings can be exciting, highly mobile affairs, especially if the bishops share the same color square. If the bishops are on opposite colors, however, you should be prepared to accept a draw.
5. Queen-and-pawn endings tend to be long and deliberate. In these games a queen can easily escort a passed pawn to the queening square with minimal difficulty.