Pronunciation: [sˈʌbstɹɪŋ] (IPA) 
The word "substring" (/ˈsʌb.strɪŋ/) is spelled as such because it is a combination of the word "sub" meaning "under" or "less than," and "string," which refers to a series of characters. The word is commonly used in computer programming to refer to a portion of a larger string or text. Its phonetic symbols, /ˈsʌb/ for "sub" and /strɪŋ/ for "string," adequately represent the pronunciation of the word as it is spoken in English.
A substring refers to a contiguous sequence of characters within a longer string. It is a concept in computer programming or text analysis where a portion of a given string is selected. The substring is a kind of smaller unit extracted from a larger textual representation.
In programming, a substring can be obtained by specifying a starting index and an ending index within the original string. The resulting substring will contain all the characters from the starting index up to, but not including, the ending index. It should be noted that the first character of the original string is usually assigned the index of 0, which implies that indexing starts from 0.
The substring operation has immense practical applications, mainly in text processing, data manipulation, or algorithmic problem-solving. It allows programmers to extract specific data or isolate particular patterns from a given string, which aids in further analysis, comparison, or transformation. Substrings are commonly employed in tasks such as searching for particular words, extracting information from delimited data, or manipulating strings for further operations.
The process of extracting substrings is a fundamental operation in many programming languages and is usually provided as a built-in function or method. Such functions typically accept the original string along with the desired starting and ending indices as input parameters and return the corresponding substring as output. These functions also handle potential error cases, such as when the specified indices are out of bounds or invalid.
