Over the years a huge amount of Promotional or Promo cards have been released for the Pokemon TCG. These are cards that cannot be purchased on their own in a store, some of them may be given away at events, some might have been given with tickets to see a Pokemon movie and others might simply have been included in blister packs, collection boxes or tins.
Since the days of Wizards of the Coast holding the license for the Pokemon Trading Card Game there have been promo cards, Wizards bought us the WOTC Black Star Promo cards, W Promotional Cards, BEST Promo cards from the e-Card series and the Southern Island promo set which accompanied the Neo series expansions.
Later on when Nintendo took over the Pokemon TCG license they bought us Poké Card Creator Pack promos which released alongside the EX series, Rumble Promo's which released alongside the Platinum series and BEST Winner cards. They also ran prerelease weekends prior to the release of main TCG expansions and gave away Prerelease cards at these events. Nintendo also introduced Jumbo Oversized promo cards which were not legal for tournament use.
There were also a number of Pokemon promo cards that could only be obtained through organised tournament play, such as the POP Series - these cards were earned and given for participants in the Play! Pokemon organised leagues and spanned from the EX Series right the way to the Platinum series.
McDonald's have partnered with Nintendo on numerous occasions to introduce promo cards too, usually coupled with a toy and given out in Happy Meals. The biggest and most consistent set of promo's has to be the Black Star Promo cards which have been running since the EX Series and continue right now in the Sun & Moon series.
Titan Cards offer a wide variety of Pokemon Promo Cards, Black Star Promo Cards, McDonalds Promo cards and other promo cards from the Pokemon TCG, old and new!