Ready . . . set . . . shop. The starting line for the annual gift-buying sprint is at the end of this week, when retailers try to lure shoppers with bargains at malls and online. The day after Thanksgiving is a public holiday in 24 states, fueling competition among major chains as consumers prepare for December holidays. A few start sales before turkey dinners can be digested fully. JC Penney opens at 3 p.m. on Thanksgiving, while Best Buy and Macy’s unlock doors at 5 p.m. Target, Walmart, Kohl's, Sears, Dick's Sporting Goods and others open at 6 p.m., followed by Kmart at 7 p.m.

Holiday hours are controversial, with critics saying workers should be allowed to stay with their families. Other stores wait until early Friday morning – sometimes very early. Mall of America, a giant complex in Bloomington, Minn., reopens at 5 a.m. after staying shut on Thanksgiving. Others resisting holiday hours include TJ Maxx, Homegoods and Office Depot.

Electronics, video games and TVs are among the most popular items on sale. Thursday night and Friday bargain-hunting action is followed by what's called "Cyber Monday" -- a term coined by the National Retail Federation in 2005 to describe the Monday after Thanksgiving, when people continue to shop online after returning to work. It's now the busiest online shopping day of the year.

While the Friday after Thanksgiving remains the symbolic start for serious holiday shopping, sales volumes in 2014 and 2015 were higher on the Saturday before Christmas. This year, with Christmas falling on a Sunday, Dec. 23 -- a Friday – could be the No. 1 day for in-person buying, the National Retail Federation predicts.

Mall executive says: "Thanksgiving is a day for families and for people we care about. We want to give this day back." -- Jill Renslow, a senior vice president at Mall of America, which had opened that day in 2013-15

Business journalist says: "Avoid buying toys over Black Friday week. We do see some good deals, but they are rare. . . . You might have better luck in the second week of December, when we see the best toy deals." – Benjamin Glaser of DealNews.com, a shopping tips site

Professor says: "Offline shopping remains quite popular. Shopping is an experience, and typically people enjoy the process of shopping – walking in the store and touching and trying on the thing you want to buy. And, the minute you buy it, it is immediately yours. You don’t have to wait for it." -- Rami Zwick, University of California-Riverside marketing professor