The English language can be confusing enough when you have two words that sound the same, but are spelled differently and have entirely different meanings. Things get even more confusing when you have words that are spelled the same, but are pronounced differently and have different meanings, as well as being interconnected with other words too. That’s exactly the case with lead and led, and this has led to a great deal of incorrect usage.
Let’s start with the basics.
Of course, things are a little more complicated than that, because lead (still rhyming with weed and need) can also be used as an adjective or a noun. When you have a team of developers working on a new iPhone app, you might have a lead programmer (adjective) and someone else who is designated as the project lead (noun). The leash for a dog is roughly synonymous with its lead (noun) as well.
When you transition to past tense, then you encounter the word led (rhymes with red or said), which can either be used on its own or as a past participle with to have. Tywin Lannister led the army into battle. The team has led the league standings for two weeks. If you are looking for the past tense version of to lead, the word will always be led.
The greatest confusion arises with the completely unrelated word lead, which also rhymes with red or said, but is not the same “lead” that we discussed above (which rhymes with weed or need). Instead, lead in this context refers to the heavy metal. It is listed as Pb on the periodic table of the elements with the atomic number 82. You’ve likely heard about lead-based paints or the idiom “get the lead out,” meaning to hurry up.
Given this, you have to rely on context to know whether the “lead” you see in writing refers to being in front (and rhymes with feed) or if it refers to the toxic metal (and rhymes with dead). The good news is that if you see “led” in writing, you can be reasonably certain it is the past-tense version of lead… unless it is in all-caps (LED), which would then refer to light-emitting diodes, the technology behind many TVs and other digital displays.
English is fun, isn’t it?