When your Partner has made an Opening bid, it usually does not pay make a double or triple pre-empt style jump in your 7-card suit (and with 6-10 points). Much better to bid your long suit up the line and try to determine Partner's strength and distribution before going "all out".
There is a much better use for such large jumps : the so-called . . . . . bid.

How often is it not that you have found the point values for Slam (in the combined hands), but once committed to it and Dummy's hand goes in the table, you see to your horror that 5, 6 , 7 or even more HCPs of Dummy are in the very suit you hold a singleton or void in. Wasted points, which could have been so much more useful in another suit.

This is what the Splinter bid can prevent.
When Partner opens (or responds in) a (usually) . . . . . . suit in which you have . . . card support, while you also hold a . . . . . . or . . . . . in one of the side suite, . . . . . raise Partner's suit directly (eg. 1♥ - 3♥), but make a . . . . . . jump into your . . . . . . or . . . . . suit.

For example :   1♥ - 4♣   or   1♥ - 3♠   or   1♠ - 4♥   or   1♣ - 1♥ - 4♦.

The Splinter bid is always above the . . . . . level, but below the actual . . . . . itself.
The Splinter bid shows :

1. The values for . . . . . and possibly . . . . . , usually . . . . points
2. . . . . card support for Partner's suit
3. A . . . . . or . . . . in the bid suit
4. Normally . . . or . . . . losers

The Splinter bid is in first instance a . . . . . . to Partner that if he holds HCPs in the specified suit, they are . . . . . , unless it is the . . . . .
Three or four small cards in the suit on the other hand, are a . . . . . sign for they can be . . . . . , providing . . . . . . . Also Partner's high cards are therefore located in . . . . . . . . . . . . .

After Partner's splinter bid take the following action :

After a first positive response to the splinter bid has been made, both players may continue with . . . . . . . . or . . . . . as they wish.

Example 1	Opener (W) ♠ - A 4 ♥ - A Q 10 8 2 ♦ - 9 4 2 ♣ - K Q 6		Responder (E) ♠ - K J 8 5 ♥ - K J 9 5 ♦ - 7 ♣ - A 9 8 4		Comment Opener with . . . . . . . . . . in the splinter suit and good values in . . . . and . . . . makes a . . . . . . response by showing his . . . . . . He then shows 2 Aces plus the . . . . . after Partner's RKC Blackwood.
	Bidding : (W) 1H - 4D - 4S - 4NT - 5S - 6H

Example 2	Opener (W) ♠ - A 4 ♥ - A Q 10 8 2 ♦ - K Q 6 ♣ - 9 4 2		Responder (E) ♠ - K J 8 5 ♥ - K J 9 5 ♦ - 7 ♣ - A 9 8 4		Comment Opener's Diamond and Club values have been reversed, and his HCPs in Diamonds are . . . . . . . . . . . With no support in Clubs a . . . . . contract is doomed. Opener therefore . . . . . . in . . . . .
	Bidding : (W) 1H - 4D - 4H - Pass

A Slam Trial bid is very similar to a . . . . . . . . . . . except in this case the bidder is not aiming for a Game contract, but investigates the possibility of . . . . . . instead.
A Slam Trial bid is the bid of a . . . . . . . after a trump suit agreement in a . . . . . . suit has been reached, either via a Game force or Invitation bid has been reached. For example :

Provided you have agreed this with your Partner the 4♣ and 4♦ are Slam Trial bids and not Cue bids showing 1st round control (as normally would be the case).

The Trial bidder is asking Partner for . . . . . . . . in the Trial suit of . . . . . . or better (or having . . . loser or less in the suit).
The response options after a Slam Trial bid are :

After a first positive response to the Slam Trial bid has been made, both players may continue with . . . . . . . or . . . . . . . as they wish.

Example 3	Opener (W) ♠ - A K J 9 5 ♥ - A 6 ♦ - A 9 8 6 3 ♣ - 4		Responder (E) ♠ - Q 10 8 2 ♥ - K 4 ♦ - K J 5 ♣ - A 7 5 4		Comment With strong support for Opener's . . . . . suit Responder makes a positive reply of . . . . , showing his . . . . . After that Opener has no hesitation in going for . . . . . .
	Bidding : (W) 1S - 3S - 4D - 5C - 6S

Example 4	Opener (W) ♠ - A K J 9 5 ♥ - A 6 ♦ - A 9 8 6 3 ♣ - 4		Responder (E) ♠ - Q 10 8 2 ♥ - K Q ♦ - 7 5 2 ♣ - A Q J 4		Comment With . . . . support for Opener's . . . . suit Responder . . . . . in . . . .
	Bidding : (W) 1S - 3S - 4D - 4S - Pass

The main strategy during the auction is to find an appropriate contract either in one of the two . . . . . suits or in . . . . . . . , and all bidding is aimed at achieving that purpose.
Consequently when a . . . . suit is raised by Partner, he sees little prospect for a contract in a . . . . . suit. But in some cases there may still be hope of finding a contract in . . . . . .

Therefore (unless the Partnership has decided otherwise) when a new suit is bid after a minor suit Game force it is not a . . . . bid showing . . . . . . and it is not a . . . . . bid.

It is instead showing a . . . . . in an attempt to find a contract in . . . . . rather than in 5 Clubs.
In above bidding sequence, the Opener has shown a . . . . . in . . . . but has denied one in . . . . . . . skipped that suit.

Likewise a bid of 3NT is . . . . . . . , and decidedly not a . . . . . . . . .

Standard 4NT Blackwood (or RKC Blackwood) however are used for . . . . . suit Slam contracts, and . . . . . bids too are appropriate.