Multiple Time Frame Analysis is the technique of analyzing several time frames of the same asset before entering a trade. This type of analysis is best done using a top-down approach, i.e. starting at a higher time frame and working your way down, via several lower time frames, until the execution time frame is reached where a trade could be entered. Traders who use this technique usually look at 3 or 4 different time frames to identify the general trend and find the best entries. They minimize their risk and improve the odds of success simply by taking the bigger picture into account. It can easily be combined with any trading strategy.
Time frames are usually several times apart. For example a day trader who trades hourly charts, could analyse the weekly (high time frame), the daily (7 times smaller), the 4 hour (6 times smaller) and finally the hourly time frame (execution time frame, 4 times smaller). TradingView has a chart layout feature with multiple charts per layout, so you can analyse an asset on multiple time frames under one tab in your browser.