In a day when video games have become a $20 billion industry driven by titles with budgets approaching those of summer movie blockbusters, some gamers are nostalgic for the simplicity of earlier times.

Modern video-game consoles may offer better graphics and more varied gameplay than ever, but the straightforwardness of classics such as "The Legend of Zelda" and "Contra" can be refreshing, said Jake Redish, 21.

"Sometimes ... I just want a sword, and I can do what I need to do," he said. "I just want to save a princess. I don't need all these other random side quests or anything; just put me on the path."

A lifelong gamer, Redish said he spends about two hours a week on an online emulation site for classic titles when he's not playing more modern games such as "World of Warcraft."

Redish is one of many gamers who continue to play 20- and 30-year-old games on Nintendos, Super Nintendos and Sega Genesis systems hooked up to the same TVs as their modern systems.

Lorin Jones, 26, said he spends most of his time playing games on his Nintendo because titles on that system require less of an investment in time (and money) to enjoy.

"The older, simpler, more direct games were more fun and suited my attention span because you could pick them up for a brief period of time, play to fulfillment and then put them down without missing anything, in life or in the game," Jones said.

Classic titles may look dated next to "Halo" and "Call of Duty," but Chattanooga-area gamers said they remain viable because they were developed with an emphasis on addictive gameplay rather than flashy graphics and computer-generated cut scenes.

Before systems like the Sega CD and Sony PlayStation, developers had to create titles to fit on plastic cartridges with a fraction of the storage space of discs. As a result, they had to be engaging on a budget, said Danny Butler, 22.

"Games on those systems focused a little more on gameplay instead of graphics," he said. "When you ... start playing stuff like the original 'Ninja Gaiden' or 'Bad Dudes,' you start to appreciate the game-making process a lot more because you have to work a lot harder to beat the game."

The steady sales for these titles is unsurprising, given their low cost compared to new releases, noted the owners of Grumpy's Music and Books and Play-N-Trade, two local shops that carry inventories of older games.

Classic titles tend to move even better than newer releases at Grumpy's, where 70 percent of the game inventory is from before the PlayStation era, said owner Doug Williams.

"Those are actually more profitable than any other new game we get in," Williams said, adding that older titles tend to sell faster as well. "We've almost quit buying newer stuff."

Local gamers said the pixelated graphics and memorable soundtracks of classic games remind them of their childhood.

That's something modern games can't replicate, no matter the technology behind them, said Kevin Terry, 25.

"One of the biggest advantages of those games is they were the first generation of games for gamers," he said. "I can go back and play those games, and no matter how bad the graphics and sound are, no matter how bad the presentation, it's comforting."

But some developers have taken note of gamers' nostalgia and are trying to recapture the magic by updating their classic franchises.

Namco, Midway and Activision have released game anthologies with reimagined versions of arcade classics such as "Joust," "Pitfall!" "Gauntlet," "Pac-Man" and "Dig Dug."

Capcom, in particular, has developed new entries for "Street Fighter," "Final Fight," "Ghosts 'n Goblins" and "Bionic Commando" that update the graphics while retaining classic gameplay. These are available via Xbox Live Arcade, PlayStation Network and Nintendo Virtual Console, all of which host large libraries of classic games users can pay to download.

The latest releases in Capcom's "Mega Man" series take the classic approach even further. "Mega Man 9" (2008) and "Mega Man 10" (2010) replicate the gameplay as well as the graphical styles of the earliest titles in the series, which began in 1987. Both games were well received, with average review scores of about 80 percent, according to the Metacritic online review aggregation site.

More developers should take note of that success, Terry said.

"They need to take a break from trying to make everything look perfect and brush it up and re-edit all the images and sound and presentation," he said. "There's so much charm in that original packaging, and it's nice to revisit those things."