In a game of Mahjong is it better to discard tiles in front of you or mix them with the other players' discarded tiles?

Here are the rules as per the Bicycle Paying Card Company:

The Pack The standard 52-card pack is used.
Object of the Game To lay matched number sets of 3 or 4 and/or sequences of 3 or more cards of the same suit to be the first player to obtain 500 total net points.
Rank of Cards
Ace (high or low), K, Q, J, 10, 9, 8, 7, 6, 5, 4, 3, 2, A.
Card Values/Scoring Score points by laying down and laying off cards as in regular Rummy, in matched number sets of 3 or 4, and in sequences of 3 or more cards of the same suit. For example, three or four 7s can be laid or a sequence of 3, 4, 5 of diamonds can be laid.
When any player gets rid of all his cards, the play immediately ends. Each player's score is then figured as follows: The player is credited with the point value of all cards that the player has showing on the table. From this figure is subtracted the point value of all cards remaining in his hand. The difference is added or subtracted from the player's score.
For example: If the cards showing for a player total 87 points, and the cards left in the player's hand total 90 points, 3 points are subtracted from the player's previous net score.
The first player whose score reaches +500 wins the game and collects from each opponent the difference between their final scores. If two or more players reach 500 on the same hand, the one with the highest score is the winner.
The Deal Deal seven cards to each player (except in the two player game, in which each player receives 13 cards). Place undealt cards face down in the center of the table, forming the stock. The top card is turned face up and is placed beside the stock as the up card to start the discard pile. The discard pile should be slightly spread, so that players can readily see all the cards it contains.
The Play Each player, beginning with the player to the left of the dealer, may draw either the top card of the stock or any card from the discard pile.
There are two conditions when drawing a card from the discard pile: 1) the player must take all the cards above the selected card and 2) the drawn card must immediately be used, either by laying it down in a set or by laying it off on a set already on the table. The remaining cards taken with the discard may be melded in the same turn or simply added to the player's hand.
Each player in turn, after drawing but before discarding, may lay down any matched set or may lay off any card that matches a set already on the table.
Cards that are laid off are kept on the table in front of the player. Sequences may not "go round the corner"; thus, A, K, Q or A, 2, 3 may be melded, but not K, A, 2. - See more at: http://www.bicyclecards.com/how-to-play/500-rum/#sthash.1oRfJip8.dpuf

Skip Bo Instructions
Object: Be the first player to play every card in your Stock pile, by playing all of your cards in numerical order, 1 to 12. For two to six players ages seven and up.
Manufacturer: International Games/Mattel

Contents: 144 numbered cards and 18 SKIP-BO cards. 162 cards total.

Beginning Play: Shuffle the deck. Each player draws a card. The person with the highest card is the dealer. The dealer deals 30 cards to each player if there are two to four players. In five to six player games, each player is dealt 20 cards. These cards are dealt face down and form each player's Stock pile. Once all Stock piles have been dealt, each player flips the top card of their Stock pile right side up and places it on top of the pile. The remaining cards not dealt are placed face down on the table to form the draw pile.
Playing Area: Each player is going to need room for four Discard piles near their Stock pile. You will also need room for four Building piles in the center of the table near the draw pile. These piles are formed as the game progresses-so make sure you leave space for them.
Stock Pile: The top card is always face up. Each player has a Stock pile.

Draw Pile: This is the pile in the center of the playing area created with all cards remaining after Stock piles are dealt.
Building Piles: Building piles are where players build the 1-12 sequences and can only be started with a 1 or a SKIP-BO (SKIP-BO cards are wild, so it would represent a 1 if used to start a sequence). Once a pile has the complete 1-12 sequence, remove it from the playing area and start a new building pile. Terrible Game if Your Name is "Bo"
Discard Pile: Each player may form sequences an any of their four discard piles. There is no limit to the number of cards in the pile, nor is there a restriction on the order. The top card of your discard piles is available for forming sequences (can be played).
Playing Skip-Bo: Play begins to the left of the dealer. Draw five cards at the beginning of your first turn (and back up to five on subsequent turns). You can use a Skip-Bo (wild card) or a 1 to begin one of the four building piles in the center of the playing area. You may continue to play cards from your hand onto the building area (1-12 in sequence only). If you play all five cards in this manner, draw back up to five (this process can repeat if needed). You may also play the top card from your Stock pile onto a building piles, and can continue to play from the Stock pile as long as the play is legal. Remember, you win by running out of your Stock pile, so play from there when you can. Your turn ends when you can't or refuse to make a play. Discard one card from your hand onto one of your four discard piles. You may play the top card of any of your discard piles on any turn after the first. Play continues clockwise.
Winning the Game: Choose a point total to play to (500 is recommended to start). The winner of each round scores 25 points for winning the round and five additional points per card remaining in each other player Stock pile.
Team Skip-Bo: You can play with partners. In team situations, you can legally play from your Stock and Discard piles as well as your partners. One catch-your partner can't talk during your turn, and you can't talk during theirs. Instead, you have to give verbal commands for any necessary actions involving their cards. If the other players catch you breaking this rule, you must take two cards from the draw pile(without looking at them) and place them on your stock pile. The round ends when all of the players on a team reach the end of their stock pile.
Special Rules:
If you draw too many cards, shuffle the extra cards into your Stock pile.
If a player draws and plays out of turn and they are caught, undo any action and play continues as normal until it reaches that players turn. On their actual turn, a penalty is enforced-they must make their play without drawing from the draw pile. If no one notices that the player played out of turn, the play is legal and no penalty in enforced.
In team play, anyone on the team can continue to play from the remaining Discard and Building piles, even if a Stock pile has been depleted.

Skip Bo Instructions
Object: Be the first player to play every card in your Stock pile, by playing all of your cards in numerical order, 1 to 12. For two to six players ages seven and up.
Manufacturer: International Games/Mattel

Contents: 144 numbered cards and 18 SKIP-BO cards. 162 cards total.

Beginning Play: Shuffle the deck. Each player draws a card. The person with the highest card is the dealer. The dealer deals 30 cards to each player if there are two to four players. In five to six player games, each player is dealt 20 cards. These cards are dealt face down and form each player's Stock pile. Once all Stock piles have been dealt, each player flips the top card of their Stock pile right side up and places it on top of the pile. The remaining cards not dealt are placed face down on the table to form the draw pile.
Playing Area: Each player is going to need room for four Discard piles near their Stock pile. You will also need room for four Building piles in the center of the table near the draw pile. These piles are formed as the game progresses-so make sure you leave space for them.
Stock Pile: The top card is always face up. Each player has a Stock pile.

Draw Pile: This is the pile in the center of the playing area created with all cards remaining after Stock piles are dealt.
Building Piles: Building piles are where players build the 1-12 sequences and can only be started with a 1 or a SKIP-BO (SKIP-BO cards are wild, so it would represent a 1 if used to start a sequence). Once a pile has the complete 1-12 sequence, remove it from the playing area and start a new building pile. Terrible Game if Your Name is "Bo"
Discard Pile: Each player may form sequences an any of their four discard piles. There is no limit to the number of cards in the pile, nor is there a restriction on the order. The top card of your discard piles is available for forming sequences (can be played).
Playing Skip-Bo: Play begins to the left of the dealer. Draw five cards at the beginning of your first turn (and back up to five on subsequent turns). You can use a Skip-Bo (wild card) or a 1 to begin one of the four building piles in the center of the playing area. You may continue to play cards from your hand onto the building area (1-12 in sequence only). If you play all five cards in this manner, draw back up to five (this process can repeat if needed). You may also play the top card from your Stock pile onto a building piles, and can continue to play from the Stock pile as long as the play is legal. Remember, you win by running out of your Stock pile, so play from there when you can. Your turn ends when you can't or refuse to make a play. Discard one card from your hand onto one of your four discard piles. You may play the top card of any of your discard piles on any turn after the first. Play continues clockwise.
Winning the Game: Choose a point total to play to (500 is recommended to start). The winner of each round scores 25 points for winning the round and five additional points per card remaining in each other player Stock pile.
Team Skip-Bo: You can play with partners. In team situations, you can legally play from your Stock and Discard piles as well as your partners. One catch-your partner can't talk during your turn, and you can't talk during theirs. Instead, you have to give verbal commands for any necessary actions involving their cards. If the other players catch you breaking this rule, you must take two cards from the draw pile(without looking at them) and place them on your stock pile. The round ends when all of the players on a team reach the end of their stock pile.
Special Rules:
If you draw too many cards, shuffle the extra cards into your Stock pile.
If a player draws and plays out of turn and they are caught, undo any action and play continues as normal until it reaches that players turn. On their actual turn, a penalty is enforced-they must make their play without drawing from the draw pile. If no one notices that the player played out of turn, the play is legal and no penalty in enforced.
In team play, anyone on the team can continue to play from the remaining Discard and Building piles, even if a Stock pile has been depleted.

When a Mahjong tile is discarder it's considered "dead" and cannot be used or picked up again unless you have a pair of the same kind and picking up the discarded tile allows you to open a "three of a kind" set. This is only if you already have two of that kind. If you do, you say "pong" and take the discarded tile to show your set.
You can't do it to create a "run", meaning three subsequential numbers of a same suit, unless you are the next one in turn to play.
Another exception is if you are calling for Mahjong, meaning using the last discarded tile to finish all the required sets that allow you to win, and declare Mahjong. Then you are allowed to call for the discarded tile.

From Wikipedia: The cards are shuffled and each player receives eight. The rest of the deck becomes the draw pile. The top card in the draw pile is turned over and placed face up next to the draw pile to form a discard pile. The upper card of the discard pile is called the Leading Card. The youngest player goes first. Starting clockwise, each player discards a card (or cards) onto the leading card, by (a) matching its color; or (b} matching its number or figure; or (c)using a SuperTaki, Switch Color, or Crazy Card. A player who cannot play draws one card from the draw pile. It may be used only in the next round. A player who is left with one card in his hand must announce "Last card!" If he fails to do this before the next player made his move, he draws 4 cards from the draw pile. The game ends when the first player has discarded his last card.

Instructions Things You'll Need

• Nintendo Game Boys
• Card Tables
• Chairs
• Nintendo Game Boy Game Link Cables
• Snacks
• Beverages
• Spiral Notebooks
• Game Boys (Color)
• UNO Card Decks
• Pencils

1. • 1 Use a deck of UNO cards. The deck has 108 cards consisting of four suits, wild cards, and word cards with directions on them.
     
   • 2 Choose a dealer by having each player pick one card. The person with the highest number is the dealer. Word cards count as zero.
     
   • 3 Deal each player seven cards and place the remaining cards face down in the middle of the table. This is the draw pile.
     
   • 4 Turn the top card of the draw pile over to form the discard pile.
     
   • 5 Take turns beginning with the player to the dealer's left and go clockwise around the table.
     
   • 6 Place one of your cards on the discard pile when it's your turn. Your card must have the same number, color or wording as the top card of the discard pile - or be a wild card.
     
   • 7 Draw a card if you cannot discard. Play the drawn card if you can. If you can't, it's the next person's turn.
     
   • 8 Announce a suit when you place a wild card on the discard pile. You can play a wild card any time it's your turn and can name any suit you wish.
     
   • 9 Announce a suit when you place a Draw Four card on the discard pile.
     
   • 10 Follow the directions of a word card that is played on the discard pile by the player preceding you. This may mean that you have to draw two cards, skip a turn or even draw four cards.
     
   • 11 Say "UNO" when you have one card left in your hand. If you forget to say UNO and another player catches you, you must draw two cards.
     
   • 12 Tally all the points when one player is out of cards. (See related eHow "How to Keep Score in UNO.")
     

Read more: How to Play UNO ' eHow.com http://www.ehow.com/how_16919_play-uno.html#ixzz1jxXQAJrS

Uno rules can be found at http://www.unorules.com/ and Pit rules at http://www.centralconnector.com/GAMES/pit.html

1. One player is chosen to be the dealer,who shuffles the deck and deals out a hand of 10 cards
2. one at a time and face down, to each player
3. Players hold their 10 cards in hand, so that other players cannot see them.
4. The remaining deck is placed face down in the center of the play area, to become the draw pile.
5. The top card of the draw pile is turned over and placed next to the draw pile, to become the discard pile.
6. Play begins with the player to the left of the dealer, and progresses to the left.
7. In turn, a player draws one card-either the top card from the draw pile or the top card from the discard pile-and adds it to the player's hand.
8. The player ends the turn by discarding one card of choice onto the discard pile.
9. Play of the first hand begins, with each player trying to complete the first Phase of the 10 Phases. Each player can make only one Phase during the game

Go to this site for more details : http://www.centralconnector.com/GAMES/phase10.html

Simple Word Rummy:
Deal 7 cards per player. In a turn, a player: draws 1 card from the draw or discard pile; plays one meld from the hand or adds to a meld on the table; and discards one.
Melds can be 3+ of the same letter; a straight of 3+ letters in a row; or a word of 2+ letters of the same color (unless there are 2+ of the same letter in the word). Adding to a meld can extend the set or straight, or change its type (straight ABC + S to word CABS), or even flip them to the other color and letters.
The round ends when a player empties his hand after discarding. He get the total of the numbers on all cards in hand of all opponents. Each player with a meld of 5+ cards gets 50 points bonus. Game is 500 points.