Skilled

Skilled is a trait in Fallout, Fallout 2, Fallout Tactics, the Fallout: New Vegas add-on Old World Blues, Van Buren, J.E. Sawyer's Fallout Role-Playing Game and Lionheart.

Fallout
You gain +10% to all skills but gain a perk only every 4 levels instead of 3.

It is supposed to also give +5 Skill Points per level, but the player never received these, only the extra +10% at character creation. As the in-game description doesn't mention the +5 skill points per level, it is not clear whether this was an intentional removal from the game, or an oversight by the designers.

Fallout 2 and Fallout Tactics
You gain +5 skill points per level but gain a perk only every 4 levels instead of 3.

Old World Blues
You gain +5 to all skills, but you suffer a -10% penalty to gained experience points.

Bugs

 * If you use this at the beginning of the game, you will have the normal effects. However, if you re-apply it before going into the wasteland, the positive effect doubles and the negative effect doesn't double, remaining at -10% Experience. The trait can also be later reapplied at The Sink for a total of 15 points to all skills, while the penalty remains at -10%.
 * In addition, if Skilled is removed via the Sink autodoc, the skill bonuses remain while the debuff is removed (this does not effect XP already missed, it merely means that the -10% penalty no longer applies).

J.E. Sawyer's Fallout Role-Playing Game
You gain an additional Tag skill. However, you gain -1 skill points every level because you often spread yourself too thin.

Lionheart
You spend more time improving your skills than a normal person does, allowing you to gain more skill points per level. The tradeoff is that you do not gain as many extra abilities. You will gain a perk one level later than you usually would (i.e., a human would gain perks once every four levels, and so on). You will get an additional 5 skill points per new experience level.

Behind the scenes

 * The image in the Fallout: New Vegas add-on Old World Blues is a modified image of the Center of Mass perk.