Shares of some of the world’s biggest retail companies—including Macy’s, Walmart, and Target—jumped on Tuesday, marking a rare day of positive trading for this struggling sector.Indeed, the retail space was up nearly across the board on Tuesday. Shares of the SPDR S&P Retail ETF XRT were up 2.44%, while the Direxion Daily Retail Bull 3x Shares ETF RETL skyrocketed 7.41%.The Amplify Online Retail ETF IBUY, VanEck Vectors Retail ETF RTH, and PowerShares Dynamic Retail Portfolio ETF PMR were all up marginally.Tuesday’s retail ETF gains can be attributed to gains from some retail giants, most of which have seen their shares dip in the last year amid a shifting shopping climate.Wal-Mart WMT, Target TGT, and Kohl’s KSS all jumped over 2% on Tuesday. Nordstrom (JWN) rose 2.96%, and Macy’s M climbed 3.72%. The Gap GPS, up 4.01%, was one of Tuesday’s biggest retail movers.Also among the day’s top movers was Dillard’s DDS, a department store chain which gained more than 7% on Tuesday after a report surfaced that suggested the stock appears to be heading for an “infinity squeeze” similar to Volkswagen’s now-legendary 2008 short squeeze (read more: Dillard's Stock Soars on Report of Imminent "Infinity Squeeze").Still, despite today’s upward movement, talk of Amazon’s AMZN apparent takeover of the entire retail world aren’t likely to stop just yet.It is true that the industry has been shaken and most likely altered forever by Jeff Bezos’ behemoth. The online retail giant dove headfirst into almost every sector imaginable, and has transformed retail into a more on-demand style world, where everything from books to snacks can be delivered to users in a few hours.But one retail player’s upward movement on Tuesday could be a sign of hope for the sector that many have all but written off. Barnes & Noble BKS posted a monster day, up over 15%, on the back of news that activist investors are set to push for a sale.At first glance that might seem like another sign that retail is struggling, but the firm is convinced that brick-and-mortar still has a place in the retail world. Barnes & Noble’s activist investors have faith that brick-and-mortar isn’t dead—it just needs to be revamped.And today’s retail movement might signal that some share this glimmer of hope.More Stock News: Tech Opportunity Worth $386 Billion in 2017 From driverless cars to artificial intelligence, we've seen an unsurpassed growth of high-tech products in recent months. Yesterday's science-fiction is becoming today's reality. Despite all the innovation, there is a single component no tech company can survive without. Demand for this critical device will reach $387 billion this year alone, and it's likely to grow even faster in the future.Zacks has released a brand-new Special Report to help you take advantage of this exciting investment opportunity. Most importantly, it reveals 4 stocks with massive profit potential. See these stocks now>> Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Amazon.com, Inc. (AMZN): Free Stock Analysis Report VANECK-RETAIL (RTH): ETF Research Reports SPDR-SP RET ETF (XRT): ETF Research Reports AMPL-ONLN RETL (IBUY): ETF Research Reports PWRSH-DYN RETL (PMR): ETF Research Reports DIR-D RTL BL 3X (RETL): ETF Research Reports Gap, Inc. (The) (GPS): Free Stock Analysis Report Wal-Mart Stores, Inc. (WMT): Free Stock Analysis Report Target Corporation (TGT): Free Stock Analysis Report Barnes & Noble, Inc. (BKS): Free Stock Analysis Report Macy's Inc (M): Free Stock Analysis Report Dillard's, Inc. (DDS): Free Stock Analysis Report Kohl's Corporation (KSS): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research