In my last post (on July 3rd) I included a video from You Tube with a women talking about making a cake.  In that video the woman used the sound “um” many times.  What is this “um”?  It is technically called a filler word or filler sound, which is an expression of hesitation or pause in speech.  You will never find “um’s” written out in books or newspapers (unless, of course, there is a conversation in quotes in the written text).  This is because when we indicate a pause in writing we have tools such as commas (,), semi-colons (;), and periods (.). These punctuation marks do the job of indicating a pause.  In speech people often use filler words and sounds within conversations to signal to others that they are pausing to think, but they are not yet finished speaking.  Filler sounds (for example: “um”, “uh”, “mm”) and filler words (for example: “like”, “you know”) are essentially meaningless words and sounds in and of themselves; they are just conversation cues.  These sounds and words, when used as fillers, do not add meaning to a sentence.  Some people use filler sounds much more often than other people do.  When some people speak they pause and use a filler sound every few words, for example: “I, um, was wondering, um, if I could, uh, borrow some, mm, money.”  When people use many filler words in their speech they are likely nervous or are searching for what to say next.  For some people using a large number of filler words and sounds becomes a habit. These people may not be aware that they are using these fillers so often.

It is best to think of filler words and sounds as having two major purposes:
1) To indicate a pause after which a person will continue talking.  For example, the short “um” sound is really just a way for the speaker to say “I’m still thinking, and I’m not willing to pass the conversation back to you just yet.  Give me a second.”
2) To indicate hesitation or the need for a moment to think.  For example, when someone is talking relatively fast filler words are often inserted into speech when the brain needs a moment to catch up the mouth.

Filler words serve the purpose of filling the otherwise dead space in conversations.  They send a message that the speaker is pausing.  Fillers are very common in everyday speech in English so you are likely to hear them particularly when talking with a native speaker of English.  I hope that this post has helped you to better understand these common sounds in the English language.