Piggybacking
Piggybacking is a video game term which describes a low-level character adventuring with high-level characters in order to obtain experience and level at an accelerated rate, a practice which is especially common in role-playing video games. Piggybacking is similar to twinking which occurs when a high-level character gives equipment to a low-level character that they couldn't normally obtain.
Many early RPGs effectively required piggybacking because new characters would join the party at their starting level and be severely under-powered compared to the rest of the characters, especially if they joined late in the game. So, when the party encounters monsters relative to the party's level, the new character would have no hope of defeating them, or even being beneficial in combat, and must rely on their more-powerful party members to do everything. However, because the powerful monsters reward a lot of experience relative to the new character, they will raise in levels very quickly until they catch up to the rest of the party.
Many later solo RPGs would alleviate the need for piggybacking by starting characters at a preset level befitting where the party would be based on test play-throughs, or dynamically leveling new characters to a value relative to the party when they first join, however, neither of these options are viable solutions in multiplayer RPGs. Depending on the player, piggybacking in an MMORPG might be seen as cheating or simply the benefit of making friends with more experienced players. However, because online games make their money from subscribers, and accelerating characters through their levels may cause players to get bored more quickly, piggybacking ultimately cuts into the company's profits. To decrease piggybacking in multiplayer games, designers impose level caps on the areas of the game where more powerful monster spawn preventing low level characters from encountering them until their higher experience isn't so beneficial. While this prevents low-level characters from getting high experience payouts from stronger monsters, it doesn't prevent high-level characters from returning to low-level areas and helping low-level characters defeat monsters more quickly, but this form of piggybacking doesn't disrupt the balance as much.
By purposely not piggybacking, players can challenge themselves with a low level run.
Personal
Most of the first RPGs I played didn't need piggybacking because you formed your complete party of characters from the onset so they gained experience at roughly the same rate. I think the first game I played which needed piggybacking was Phantasy Star III: Generations of Doom, where you're frequently getting new characters at level one. I never really thought much of having to do this because, while it wasn't uncommon for new characters in the game to be killed for the first few battles, they raised levels so quickly, it wasn't much trouble to deal with. The first game I remember playing which alleviated was Final Fantasy VI, although, I didn't even notice it until someone pointed it out to me. At first, I didn't like the game doing this as I felt like the game was awarding you levels you hadn't earned, but now I see it was a preferred mechanic.
