Alexander Graham Bell is credited with inventing the telephone and was awarded the first U.S. patent for it in 1876. However, the invention was surrounded by controversy and competing claims, notably from Elisha Gray, who filed a patent for a similar device on the very same day. There’s also evidence that Antonio Meucci developed an early voice-communication apparatus in the 1860s and filed a caveat (a preliminary patent filing) for his “teletrofono” in 1871.
So while Alexander Graham Bell is most widely recognized as the inventor of the telephone, the full story involves multiple contributors and legal battles over patent rights.