Ping Pong is the final stage of the Bill Process. Amendments made by the Second House are reconciled to the text originally produced by the First House.
The First House will vote on whether to accept, reject or offer their own amendments in lieu of the Second House Amendments, which are then sent back to the Second House.
In turn, the Second House can accept, reject, withdraw or offer their own amendments in lieu. Newly proposed amendments in lieu are then returned to the First House, where the cycle repeats.
The back and forward exchange inspires the name 'Ping Pong'. Ping Pong continues until either mutually agreeable final text is created or (extremely rarely) the Bill is abandoned.
These Bills have passed through the line by line assessment and amendment by Bill Committee. The Bill can now move to Report stage, where amendments and clauses can be tabled by any MP.
The Government will table contentious amendments and clauses at Report stage, where they may be defeated if sufficient Government backbenchers rebel.
Third Reading often takes place immediately after report stage, and is usually a formality of valedictory speeches. This would then conclude the Bill Process in the First House, and the Bill will be sent to the Second House for further review and amendment.
These bills have passed the first substantive debate on the initial draft of the Bill (Second Reading) and are now in the process of review and amendment of bill text by a Bill Committee. For the Commons, Bill Committees are formed of around 20 MPs, whereas in the Lords, a Committee of the Whole House is usually formed.
For Commons Private Members Bills, the most difficult hurdle is to pass Second Reading, due to lack of time for the debate. Since 1986, every Government Bill has passed Second Reading.
These bills have been laid before Parliament, but have not begun the Bill Process. A Short Title and Long Title (summary) of the Bill will have been provided, though a full text of the Bill may not have been tabled.
For Commons Private Members' Bills, unless a high position on the Order Paper has been secured for the Second Reading Debate (or unanimous consent is expected), it is unlikely that the Bill will progress further from this point. Often only Ballot Bills (which have priority for Second Reading) will have the opportunity to progress.