Pandas

1Series & DataFramesThe two core pandas structures, how the index works, and how to inspect a new table.7 min 2Reading & writing Excel, CSV and SQLLoad and save data reliably across CSV, multi-sheet Excel workbooks and SQL databases.7 min 3Selecting & filteringPick rows and columns precisely with loc, iloc, boolean masks and query.6 min 4Cleaning dataFix missing values, duplicates, wrong types and messy text so your analysis can be trusted.7 min 5Dates, time series & resamplingParse dates, use the .dt accessor, resample to weeks or months and compute rolling metrics.6 min 6GroupBy, merge & pivotAggregate with groupby, combine tables with merge and build cross-tabs with pivot_table.6 min 7Reshaping: melt, pivot_table, stack & unstackConvert between wide and long formats with melt, pivot, pivot_table, stack and unstack.7 min 8Performance: categoricals, vectorising & method chainingMake pandas code faster and cleaner with category dtype, vectorised logic and method chains.7 min